A Late Pleistocene coastal ecosystem in French Guiana was hyperdiverse relative to today.

Warmer temperatures and higher sea level than today characterized the Last Interglacial interval [Pleistocene, 128 to 116 thousand years ago (ka)]. This period is a remarkable deep-time analog for temperature and sea-level conditions as projected for 2100 AD, yet there has been no evidence of fossil assemblages in the equatorial Atlantic. Here, we report foraminifer, metazoan (mollusks, bony fish, bryozoans, decapods, and sharks among others), and plant communities of coastal tropical marine and mangrove affinities, dating precisely from a ca. 130 to 115 ka time interval near the Equator, at Kourou, in French Guiana. These communities include ca. 230 recent species, some being endangered today and/or first recorded as fossils. The hyperdiverse Kourou mollusk assemblage suggests stronger affinities between Guianese and Caribbean coastal waters by the Last Interglacial than today, questioning the structuring role of the Amazon Plume on tropical Western Atlantic communities at the time. Grassland-dominated pollen, phytoliths, and charcoals from younger deposits in the same sections attest to a marine retreat and dryer conditions during the onset of the last glacial (ca. 110 to 50 ka), with a savanna-dominated landscape and episodes of fire. Charcoals from the last millennia suggest human presence in a mosaic of modern-like continental habitats. Our results provide key information about the ecology and biogeography of pristine Pleistocene tropical coastal ecosystems, especially relevant regarding the-widely anthropogenic-ongoing global warming.

How to fill the biodiversity data gap: Is it better to invest in fieldwork or curation?

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream results. Understanding how best to fill existing gaps and account for biases is necessary to improve our current information most effectively. Two current main approaches for obtaining and improving data include (1) curation of biological collections, and (2) fieldwork. However, the comparative effectiveness of these approaches in improving biodiversity data remains little explored. We used the Flora de Bogotá project to study the magnitude of change in species richness, spatial coverage, and sample coverage of plant records based on curation versus fieldwork. The process of curation resulted in a decrease in species richness (synonym and error removal), but it significantly increased the number of records per species. Fieldwork contributed to a slight increase in species richness, via accumulation of new records. Additionally, curation led to increases in spatial coverage, species observed by locality, the number of plant records by species, and localities by species compared to fieldwork. Overall, curation was more efficient in producing new information compared to fieldwork, mainly because of the large number of records available in herbaria. We recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity, to identify bias and gaps at the regional scale that can then be targeted with fieldwork. The stepwise strategy would enable fieldwork to be planned more cost-effectively given the limited resources for biodiversity exploration and characterization.

Lithospheric delamination as the driving mechanism of intermediate-depth seismicity in the Bucaramanga Nest, Colombia.

The Bucaramanga nest (BN) is an area of exceptionally strong intermediate-depth seismicity localized in a narrow zone at 150-170 km depth beneath the continental plate in Colombia. To explain the very unusual mantle seismicity cluster in this area, we built a seismic velocity model in the vicinity of BN with the use of local earthquake tomography and developed a numerical hydromechanical model. Our seismic model shows a strong high-velocity anomaly at 130-167 km coinciding with the BN seismicity. The relocated seismicity can be separated in two clusters. We propose that the upper BN cluster at ~ 130 km depth is attributed to dehydration embrittlement, whereas the lower BN cluster at ~ 150 km depth coinciding with the high-velocity body is caused by lithospheric delamination, creating a "drip" that falls down over the subducting oceanic plate, enhancing fluid release from the slab, potentially increasing seismicity.

Morphological analysis of plasma electrolytic oxidation coatings formed on Ti6Al4V alloys manufactured by electron beam powder bed fusion.

This study investigates and compares plasma electrolytic oxidation (PEO) coatings produced on wrought Ti6Al4V alloy substrates with those resulting from electron beam powder bed fusion (PBF-EB). For a duration of 1000 s, a phosphate/silicate electrolyte with a current density of 50 A/cm2 was employed to fabricate the coatings. Surface and polished cross-sections of the coated specimens underwent SEM and X-ray diffraction (XRD) analyses. The obtained coatings exhibit differences of up to approximately 18% in thickness and formation, as well as in their anatase phase. The anatase phase is present at a level of 54.09% in the substrates processed by PBF-EB and 38.54% in wrought substrates. After 1000 s of PEO, the coatings formed on the wrought substrates exhibited higher porosity and larger pores (>1 µm) compared to those produced on the PBF-EB specimens. The PBF-EB coatings had lower porosity because they contained fewer pores larger than 1 µm. The findings imply that the unique microstructural arrangement of PBF-EB-produced additively made Ti6Al4V materials plays a significant impact in the development and morphological properties of PEO oxide coatings.

Tsallis q-Statistics in Seismology.

Non-extensive statistical mechanics (or q-statistics) is based on the so-called non-additive Tsallis entropy. Since its introduction by Tsallis, in 1988, as a generalization of the Boltzmann-Gibbs equilibrium statistical mechanics, it has steadily gained ground as a suitable theory for the description of the statistical properties of non-equilibrium complex systems. Therefore, it has been applied to numerous phenomena, including real seismicity. In particular, Tsallis entropy is expected to provide a guiding principle to reveal novel aspects of complex dynamical systems with catastrophes, such as seismic events. The exploration of the existing connections between Tsallis formalism and real seismicity has been the focus of extensive research activity in the last two decades. In particular, Tsallis q-statistics has provided a unified framework for the description of the collective properties of earthquakes and faults. Despite this progress, our present knowledge of the physical processes leading to the initiation of a rupture, and its subsequent growth through a fault system, remains quite limited. The aim of this paper was to provide an overview of the non-extensive interpretation of seismicity, along with the contributions of the Tsallis formalism to the statistical description of seismic events.

Additive manufacturing of Ti6Al4V alloy via electron beam melting for the development of implants for the biomedical industry.

Additive Manufacturing (AM) or rapid prototyping technologies are presented as one of the best options to produce customized prostheses and implants with high-level requirements in terms of complex geometries, mechanical properties, and short production times. The AM method that has been more investigated to obtain metallic implants for medical and biomedical use is Electron Beam Melting (EBM), which is based on the powder bed fusion technique. One of the most common metals employed to manufacture medical implants is titanium. Although discovered in 1790, titanium and its alloys only started to be used as engineering materials for biomedical prostheses after the 1950s. In the biomedical field, these materials have been mainly employed to facilitate bone adhesion and fixation, as well as for joint replacement surgeries, thanks to their good chemical, mechanical, and biocompatibility properties. Therefore, this study aims to collect relevant and up-to-date information from an exhaustive literature review on EBM and its applications in the medical and biomedical fields. This AM method has become increasingly popular in the manufacturing sector due to its great versatility and geometry control.

Expansion of the genus Massinium (Holothuroidea: Thyonidae) to the American continent and description of a new species / Expansión del género Massinium (Holothuroidea: Thyonidae) al continente americano y descripción de una nueva especie

Introduction: The genus Massinium includes 11 species, most from the Indo Pacific Ocean, and had not previously being reported from the American continent. Objective: To present the new record of the genus Massinium and describe a new species of this genus. Methods: Material collection was done by SCUBA-diving to depths of a maximum of 9 m. Results: Massinium ocumichoensis sp. nov. is described from seven specimens that extends the range of the genus to the American continent (Guerrero, Michoacan and Jalisco, Mexico). The new species lives in sandy-rocky substrata, from 2 to 16 m deep. It is distinguished from its congeneric species by a combination of morphological characters: mid-dorsal slightly bigger pseudobuttons (40-60 μm), and tables in the body wall. A taxonomic key for distinguishing the species of Massinium is provided. Conclusions: The geographic range of the genus Massinium is extended to the Mexican Pacific with M. ocumichoensis sp. nov.

Introducción : El género Massinium incluye 11 especies, la mayoría del Océano Indo-Pacífico, y no se había reportado previamente en el continente americano. Objetivo: Presentar el nuevo registro del género Massinium y describir una nueva especie de este. Métodos: La recolección de material se realizó mediante buceo a una profundidad máxima de 9 m. Resultados: Massinium ocumichoensis sp. nov. se describe a partir de siete ejemplares que extiende el rango de distribución del género al Continente Americano (Guerrero, Michoacán y Jalisco, México). La nueva especie vive en sustratos arenosos-rocosos, de 2 a 16 m de profundidad. Se distingue de sus especies congenéricas por una combinación de caracteres morfológicos: pseudobotones de la zona dorsal media ligeramente más grandes (40-60 μm) y tablas en la pared del cuerpo. Se proporciona una clave taxonómica para distinguir las especies de Massinium. Conclusiones: El rango geográfico del género Massinium se extiende al Pacífico mexicano con M. ocumichoensis sp. nov.

Morphological variability of recent species of the order Cassiduloida (Echinodermata: Echinoidea) of Mexico / Variabilidad morfológica de especies recientes del orden Cassiduloida (Echinodermata: Echinoidea) de México

Introduction: In Mexico, there are two recorded living species of Cassiduloida: Cassidulus caribaearum and Rhyncholampas pacifica. Most of the taxonomic studies on cassiduloids have used external morphology, pedicellariae and morphometric characters; however, the intraspecific variation of quantitative and qualitative characters has been poorly evaluated. Objective: To compare the basic morphology of R. pacifica and C. caribaearum. Methods: We examined a total of 2 158 specimens of R. pacifica and C. caribaearum, selecting 50 to evaluate shape and size with linear regression and Principal Component analysis. We selected an additional 62 specimens per species to identify significant character correlations and morphological groups within species. Results: There is a direct relationship between Test length and Test width. Test height/Test width, and Total length (oral view)/Distance from the ambitus to the peristome apex, are the two main ratios to distinguish both species. C. caribaearum is more dorsoventrally compressed and has a round peristome base; versus R. pacifica has a tall and triangular one. There are four morphological groups of C. caribaearum and two groups for R. pacifica. Conclusions: These two species can be distinguished with reliable morphological characters, in which peristome shape suggests that R. pacifica is more adapted to burrowing deeper into certain types of substratum.

Introducción: En México, hay dos especies vivientes registradas de Cassiduloida: Cassidulus caribaearum y Rhyncholampas pacifica. La mayoría de los estudios taxonómicos sobre casiduloides han utilizado morfología externa, pedicelarios y caracteres morfométricos; sin embargo, la variación intraespecífica de caracteres cuantitativos y cualitativos ha sido poco evaluada. Objetivo: Comparar la morfología básica de R. pacifica y C. caribaearum. Métodos: Examinamos un total de 2 158 especímenes de R. pacifica y C. caribaearum, seleccionando 50 para evaluar la forma y el tamaño con regresión lineal y análisis de componentes principales. Seleccionamos 62 especímenes adicionales por especie para identificar correlaciones significativas de caracteres y grupos morfológicos dentro de las especies. Resultados: Existe una relación directa entre la longitud de la testa y el ancho de la testa. La Altura de la testa / Anchura de la testa y la Longitud total (vista oral) / Distancia desde el ambitus hasta el ápice del peristoma, son las dos proporciones principales para distinguir ambas especies. C. caribaearum está más comprimido dorsoventralmente y tiene una base del peristoma redonda; versus R. pacifica que tenía una alta y triangular. Hay cuatro grupos morfológicos de C. caribaearum y dos grupos de R. pacifica. Conclusiones: Estas dos especies se pueden distinguir con caracteres morfológicos confiables, en los que la forma del peristoma sugiere que R. pacifica está más adaptada para excavar más profundamente en ciertos tipos de sustratos.

Redescription of the sea urchin Eucidaris thouarsii (Cidaroida: Cidaridae) based on material from the Mexican Pacific / Redescripción del erizo de mar Eucidaris thyarsii (Cidaroida: Cidaridae) basado en material del Pacífico mexicano

Introduction: Eucidaris thouarsii is a cidaroid sea urchin found from the Gulf of California to Ecuador. Its taxonomy is based on general descriptions of test shape, primary and secondary spines, the Aristotle's lantern, apical system, and peristome. Objective: To redescribe E. thouarsii with detailed descriptions, adding new taxonomic characters. Methods: We examined and reidentified 792 specimens, measuring and analyzing in detail structures of taxonomic value. Results: The horizontal diameter of the test ranges from 2.8 to 48.45 mm; the peristome corresponds to 40-60 % of that diameter, proportionally bigger than the apical system; the interambulacral areas are four times larger than the ambulacral areas. The variation of the pedicellariae is shown with scanning electron microscopy. The specimens of the Mexican oceanic islands are markedly different when compared to those of the mainland. Conclusions: Eucidaris thouarsii has five well differentiated secondary spines, and also specific regionalization; the apical system varies according to the size of the Horizontal Diameter of the Test; the globiferous pedicellariae have intraspecific differences; and the tridentate pedicellariae are specifically regionalized.

Introducción: Eucidaris thouarsii es una especie de erizo de mar, cidárido presente desde el Golfo de California hasta Ecuador. Su taxonomía está basada en descripciones generales de la forma de la testa, espinas primarias y secundarias, la linterna de Aristóteles, el sistema apical y peristoma. Objetivo: Redescribir E. thouarsii con descripciones detalladas, añadiendo nuevos caracteres taxonómicos. Método: Examinamos y reidentificamos 792 ejemplares, midiendo y analizando a detalle estructuras de valor taxonómico. Resultados: El diámetro horizontal de la testa va de 2.8 a 48 mm; el peristoma corresponde entre el 40-60% del diámetro horizontal de la testa, proporcionalmente más grande que el sistema apical; el área interambulacral es cuatro veces más grande que el área ambulacral. La variación en los pedicelarios se muestra con microscopía electrónica de barrido. Los ejemplares de las islas oceánicas mexicanas son claramente diferentes, comparados con los de la costa. Conclusiones: Eucidaris thouarsii tiene cinco tipos bien definidos de espinas secundarias que se encuentran regionalizadas en la testa, el sistema apical varía de acuerdo con el diámetro horizontal de la testa, los pedicelarios globíferos tienen diferencias intraespecíficas y los pedicelarios tridentados estas específicamente regionalizados.

Nuevos registros de la familia Cucumariidae (Holothuroidea: Dendrochirotida) en el Pacifico mexicano / New records of the family Cucumariidae (Holothuroidea: Dendrochirotida) for the Mexican Pacific

Introducción: Los cucumáridos son un grupo cosmopolita de pepinos de mar que habitan en sedimentos rocosos-arenosos, desde la zona intermareal hasta la zona abisal. Objetivo: Presentar nuevos registros para el Pacífico mexicano. Métodos: Se utilizó estereoscopio y microscopía electrónica de barrido para mostrar la morfología externa e interna de especímenes de la colección de la Universidad Nacional Autónoma de México. Resultados: Presentamos una sinopsis taxonómica de cucumáridos en el Pacífico mexicano y revisamos su taxonomía en las espículas. Se confirma la identidad taxonómica de Pseudocnus curatus, Pseudocnus dubiosus y Pseudocnus lubricus y se descarta la presencia de Trachythyone peruana. Conclusiones: Se presentan cuatro nuevos registros para el Pacífico mexicano: Leptopentacta nina, Pseudocnus curatus, Pseudocnus dubiosus y Pseudocnus lubricus.

Introduction: Cucumarids are a cosmopolitan group of sea cucumbers that inhabit rocky-sandy sediments, from the intertidal zone to the hadal zone. Objective: To present new records for the Mexican Pacific. Methods: We applied stereoscope and scanning electron microscopy to external and internal morphology of specimens in the collection of the National Autonomous University, Mexico. Results: We present a taxonomic synopsis of cucumarids in the Mexican Pacific and review their taxonomy on the ossicles. The taxonomic identity of Pseudocnus curatus, Pseudocnus dubiosus and Pseudocnus lubricus is confirmed, and the presence of Trachythyone peruana is ruled out. Conclusions: Four new records are presented for the Mexican Pacific: Leptopentacta nina, Pseudocnus curatus, Pseudocnus dubiosus and Pseudocnus lubricus.

Global variation of seismic energy release with oceanic lithosphere age.

Variations in Mid Ocean Ridge seismicity with age provide a new tool to understand the thermal evolution of the oceanic lithosphere. The sum of seismic energy released by earthquakes during a time, and for an area, is proportional to its lithospheric age. Asthenospheric temperatures emerge on ridge centers with new crust resulting in high seismic activity; thus, the energy released sum is highest on the young lithosphere and decreases with age. We propose a general model that relates the systematic variation of seismic energy released with the lithospheric age. Our analysis evaluates the main physical factors involved in the changes of energy released sum with the oceanic lithosphere age in MOR systems of different spreading rates. These observations are substantiated based on three cross-sections of the East Pacific Rise, six sections in the Mid Atlantic Ridge, and three profiles in the Central Indian Ridge. Our global model provides an additional tool for understanding tectonic processes, including the effects of seismicity and mid-plate volcanism, and a better understanding of the thermal evolution for the young oceanic lithosphere.

Extension of the thoracic spine sign as a diagnostic marker for thoracic trauma.

INTRODUCTION: The initial evaluation of patients with thoracic trauma remains a diagnostic challenge for surgery and emergency physicians. Chest sonography plays a key role in the approach for this group of patients, through extended and focused evaluation with trauma sonography (E-FAST). OBJECTIVES: To establish the diagnostic performance of the extension of the thoracic spine sign using chest sonography in trauma to diagnose hemothorax and compare it with the gold standard test chest computed tomography (CT). METHODS: This prospective observational study was conducted over 1 year. Patients who attended the emergency room with closed or penetrating thoracic or thoraco-abdominal trauma, an indication for a chest CT as part of a diagnostic evaluation according to institutional protocols, and who previously underwent a chest sonogram to determine the extent of the thoracic spine sign to diagnose hemothorax. Sonographic results were compared to a radiologist's interpretation of the chest CT. The radiologists were blinded to the initial sonogram interpretation. RESULTS: Seventy-six patients were enrolled with an average age of 32 years. They mainly had closed trauma, which accounted for 77.6% of samples, and 222 chest images were taken. The sensitivity and specificity for this study were 78.7% and 92.6%, respectively, with a positive predictive value and negative predictive value of 65% and 97.8%, respectively. CONCLUSIONS: Extension of the thoracic spine sign allows rapid identification of the presence, and more precisely, the absence of pleural effusion. This, therefore, allows an appropriate diagnosis and approach in the emergency room in patients with chest trauma.

First molecular evidence of Theileria cervi infection in white-tailed deer (Odocoileus virginianus) in Mexico.

Theileria cervi is a tick-borne protozoan that infects different deer species around the world. Clinical diseases due to Theileria cervi have been reported in white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) in the USA, however, information about this parasite has not been documented in Mexico. Here, blood samples from three white-tailed deer (Odocoileus virginianus) from a region in northeastern Mexico were analyzed by blood smear, PCR, and DNA sequencing. The results confirmed the presence of T. cervi for the first time in white-tailed deer in Mexico.

Structural and Electronic Characterization of a Photoresponsive Lanthanum(III) Complex Incorporated into Electrospun Fibers for Phosphate Ester Catalysis.

Herein, we present the light-induced synthesis and characterization of a La3+/spiropyran derivative complex (LaMC) and its application as a catalyst when incorporated into electrospun polycaprolactone (PCL) fibers. In addition to experimental methods, computational calculations were also essential to better understand the structure and electronic characteristics of LaMC. The LaMC complex was identified as a 10-coordinated structure with the La3+ ion coordinated by four oxygens from the phenolate and the carbonyl of the carboxyl acid group from both MC ligands and by six oxygens from three nitrate ligands. In addition, LaMC was capable of getting reversibly isomerized by UV or visible light cycling. All PCL fibers were successively obtained, and their morphologies, surface properties, and catalytic behavior were studied. Results showed that PCL/LaMC fibers were capable of catalyzing bis(2,4-dinitrophenyl)phosphate degradation efficiently. Complete hydrolysis was accomplished in only 1.5 days relative to the half-life time of 35 days for the uncatalyzed hydrolysis at pH 8.1 and 25 °C.

Massive replica exchange Monte Carlo algorithm: a tool to access high pressure thermodynamics of hard systems.

We have explored the idea of producing the equilibrium equation of state, i.e. the pressure as a function of packing fraction, ßP(φ), of a confined system up to very high pressures to yield the configuration that leads to the maximum packing fraction. For this purpose we have massively implemented the replica exchange Monte Carlo algorithm in graphics processing units (GPUs), in such a way that each GPU core handles a single simulation cell. This yields a very easy scheme to implement parallelization for a very large amount of replicas (thousands), which densely sample configuration space. We have tested this idea with a very well studied system, i.e. discs confined in a circular cavity, for a number of particles N ≤ 125. In all cases, our outcomes for configurations having maximum packing fractions are in perfect agreement with those already reported and conjectured optimal in the literature, for which there is no formal mathematical proof, strongly suggesting that they are indeed optimal configurations. Furthermore, in most cases, we have obtained the same function ßP(φ), by compressing loose random configurations and by decompressing copies of the configuration having the largest packing fraction. This reveals numerically that the so obtained maximum packing configurations are the correct answer.

Underlying Physics of Conductive Polymer Composites and Force Sensing Resistors (FSRs). A Study on Creep Response and Dynamic Loading.

Force Sensing Resistors (FSRs) are manufactured by sandwiching a Conductive Polymer Composite (CPC) between metal electrodes. The piezoresistive property of FSRs has been exploited to perform stress and strain measurements, but the rheological property of polymers has undermined the repeatability of measurements causing creep in the electrical resistance of FSRs. With the aim of understanding the creep phenomenon, the drift response of thirty two specimens of FSRs was studied using a statistical approach. Similarly, a theoretical model for the creep response was developed by combining the Burger's rheological model with the equations for the quantum tunneling conduction through thin insulating films. The proposed model and the experimental observations showed that the sourcing voltage has a strong influence on the creep response; this observation-and the corresponding model-is an important contribution that has not been previously accounted. The phenomenon of sensitivity degradation was also studied. It was found that sensitivity degradation is a voltage-related phenomenon that can be avoided by choosing an appropriate sourcing voltage in the driving circuit. The models and experimental observations from this study are key aspects to enhance the repeatability of measurements and the accuracy of FSRs.

Underlying Physics of Conductive Polymer Composites and Force Sensing Resistors (FSRs) under Static Loading Conditions.

Conductive polymer composites are manufactured by randomly dispersing conductive particles along an insulating polymer matrix. Several authors have attempted to model the piezoresistive response of conductive polymer composites. However, all the proposed models rely upon experimental measurements of the electrical resistance at rest state. Similarly, the models available in literature assume a voltage-independent resistance and a stress-independent area for tunneling conduction. With the aim of developing and validating a more comprehensive model, a test bench capable of exerting controlled forces has been developed. Commercially available sensors-which are manufactured from conductive polymer composites-have been tested at different voltages and stresses, and a model has been derived on the basis of equations for the quantum tunneling conduction through thin insulating film layers. The resistance contribution from the contact resistance has been included in the model together with the resistance contribution from the conductive particles. The proposed model embraces a voltage-dependent behavior for the composite resistance, and a stress-dependent behavior for the tunneling conduction area. The proposed model is capable of predicting sensor current based upon information from the sourcing voltage and the applied stress. This study uses a physical (non-phenomenological) approach for all the phenomena discussed here.

Breathing of the Nevado del Ruiz volcano reservoir, Colombia, inferred from repeated seismic tomography.

Nevado del Ruiz volcano (NRV), Columbia, is one of the most dangerous volcanoes in the world and caused the death of 25,000 people in 1985. Using a new algorithm for repeated tomography, we have found a prominent seismic anomaly with high values of the Vp/Vs ratio at depths of 2-5 km below the surface, which is associated with a shallow magma reservoir. The amplitude and shape of this anomaly changed during the current phase of unrest which began in 2010. We interpret these changes as due to the ascent of gas bubbles through magma and to degassing of the reservoir. In 2011-2014, most of this gas escaped through permeable roof rocks, feeding surface fumarole activity and leading to a gradual decrease of the Vp/Vs ratio in the reservoir. This trend was reversed in 2015-2016 due to replenishment of the reservoir by a new batch of volatile-rich magma likely to sustain further volcanic activity. It is argued that the recurring "breathing" of the shallow reservoir is the main cause of current eruptions at NRV.

Distribution and trends of hematology and oncology research in Latin America: A decade of uncertainty.

BACKGROUND: Although hematology and oncology research is a highly relevant and evolving field, research contributions by Latin American countries, apart from Brazil, remain unclear. METHODS: The authors performed a bibliometric analysis through a methodical search of the Latin American abstracts presented at 4 main hematology and oncology annual scientific meetings from 2000 to 2010. Latin American regional and national productivity was described through distribution and trend analyses; the subsequent percentage of full-text publications was also determined. RESULTS: In total, 2871 abstracts were identified, of which 1972 abstracts (68.7%) were determined to be original Latin American research and were included in the analysis. Brazil produced by far the most abstracts, with 51.1% of the total, followed by Argentina, Mexico, Peru, Chile, and Uruguay. Together, these 6 countries accounted for 95.2% of the abstracts. Latin America had a positive trend, registering an average increase of 21.5 abstracts per year (P < .001). Significant positive growth trends were observed for Brazil, Mexico, Peru, and Uruguay. Argentina and Uruguay were the most productive countries when considering the rate of abstract presentation per population. The full-text publication rate was 17.9%, and the median time to publication after presentation was 1 year. Brazil prevailed as the leading publishing country (60%), followed by Mexico, Argentina, Peru, Chile, and Cuba, all of which together published 96% of the full-text articles. CONCLUSIONS: Hematology and oncology research is increasing in Latin America, but this contribution remains limited to a few countries. There is also a low rate of full-text articles derived from annual scientific meetings. More extensive research is recommended.

Embryo transfer in angus and brahman recipient cows: effect of two methods of estrus synchronization on induced estrus and pregnancy

Over a 3-year period, 88 Angus and 87 Brahman cows were used as recipients to determine the effects of breedtype and method of estrous synchronization on induced estrus and subsequent pregnancy following embryo transfer. Estrus was synchronized in recipients using either prostaglandin-F2α (PGF; Lutalyse) or progestogen (PRO; Syncro-Mate-B). Recipients were treated (im) with PGF on day -11 (25 mg), 0 (12.5 mg), and 1 (12.5 mg). Recipients were treated with PRO on day -9 (6 mg norgestomet ear implant and 2 mL [im] of 3 mg of norgestomet and 5 mg of estradiol valerate) and the ear implant was removed on day 0. Embryos were randomly transferred to recipients synchronous +24 to -24 h with a 7-d embryo. Both synchronization methods (PGF vs. PRO) were similarly effective in inducing estrus (89.8 vs. 86.7 percent). Percentage of induced estrus was similar between Brahman (91.0 percent) and Angus (85.6 percent). Recipients treated with PGF had a longer (P = 0.001) interval to estrus than PRO treated recipients (77.4 vs. 60.1 h). Estrus response in Angus was earlier (P = 0.043) than in Brahman (65.4 vs. 72.2 h). Neither breed (P = 0.97; Angus 49 percent 35/72 and Brahman 54 percent 38/70) nor estrus synchronization treatment (P = 0.23; PRO 49 percent 35/72 and PGF 54 percent 38/70) affected pregnancy rate. Pregnancy rates in recipients closely synchronized (0 h) was 60.0 percent, within +12 and -12 h was 56.0 percent, and within +24 and -24 h was 51.5 percent. Four-year-old recipients had lower pregnancy rates (34.8 percent) than did 5-year-old (60.9 percent) or greater than 6-year-old (70.0 percent) recipients. These results indicate that PGF, when administered as a split-second dose, is as effective in synchronizing estrus in Angus and Brahman as PRO. Asynchrony of embryo age with recipient stage of cycle up to +24 or -24 h did not significantly affect pregnancy rates.

Durante tres años, vacas receptoras Angus (88) y Brahman (87) se utilizaron para determinar los efectos de raza y método de sincronización sobre las características del celo inducido y la preñez subsecuente a la transferencia embrionaria. El celo fue sincronizado en las receptoras utilizando PGF2α (Lutalyse®) o progesterona (PRO; Syncro-Mate-B). Un grupo de receptoras fue inyectado (im) con PGF los días 11 (25 mg), 0 (12,5 mg), y 1 (12,5 mg). Otro grupo fue tratado con PRO el dia -9 (implante auricular con 6 mg norgestomet e inyectadas (im) con 2 mL con 3 mg de norgestomet y 5 mg de valerato de estradiol), el implante fue removido el día 0. Los embriones fueron transferidos al azar a las receptoras en sincronía +24 a -24 h con embriones de 7-d de edad. Ambos métodos de sincronización (PGF vs. PRO) fueron similares en la inducción del celo (89,8 vs. 86,7 por ciento). El porcentaje de celos inducidos fue similar en Brahman (91,0 por ciento) y Angus (85,6 por ciento). Las receptoras tratadas con PGF presentaron un intervalo al celo más largo (P = 0,001) que aquellas tratadas con PRO (77,4 vs. 60,1 h). El intervalo al estro post-tratamiento fue más corto en la vacas Angus expresaron celo más temprano (P = 0,043) que las Brahman (65,4 vs. 72,2 h). La tasa de preñez no fue afectada por la raza (Angus 49 por ciento 35/72 y Brahman 54 por ciento 38/70; P = 0,97) ni por el tratamiento de sincronización (PRO 49 por ciento 35/72 y PGF 54 por ciento 38/70; P = 0,23). Las tasas de preñez en receptoras de sincronización cercana (0 h) fue del 60,0 por ciento, entre +12 y -12 h fue del 56,0 por ciento, y entre +24 y -24 h fue del 51,5 por ciento. Las receptoras de cuatro años de edad presentaron tasas de preñez menores (34,8 por ciento) que las de cinco (60,9 por ciento) o las de 6 o más años de edad (70,0 por ciento). Los resultados indican que cuando la segunda aplicación de PGF se administra dividida en dos dosis, es tan efectiva para sincronizar...