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Ongoing studies of a multiple track-bearing horizons from massive excavations in the Jinju Formation (Lower Cretaceous) of South Korea have yielded a remarkable diversity of avian, non-avian dinosaur, pterosaur, crocodilian and mammal tracks, many very small and well preserved. Here we report diminutive, didactyl tracks (~1.0 cm long) assigned to a new dromaeosaurid ichnogenus Dromaeosauriformipes, which resembles the larger, but still quite small, ichnogenus Dromaeosauripus, also from the same formation only 30 km away. These diminutive tracks are consistent with the foot size of smaller dromaeosaurid taxa like Early Cretaceous Microraptor from China, and may represent diminutive species or juveniles of larger species. The association of tracks with lakeshore sediments is consistent with the evidence that Microraptor was a fish eater. Two trackways and isolated tracks indicate variable trackmaker gaits and speeds. If oviparous, as assumed for most non-avian dinosaur neonates, the trackmakers must have hatched from tiny eggs. Previous studies of the Korean Cretaceous indicate the presence of other diminutive (~1.0 cm long) theropod tracks (Minisauripus). Such occurrences strongly suggest that small tracks attributed to juveniles, or very small tetrapod species, are more common than previously supposed especially where suitable preservation conditions prevailed.

A relatively small number of tetrapod tracksites from Zhejiang Province fills out the fossil record from that region, which is also known to have yielded both saurischian (titanosauriform, coelurosaur) and ornithischian (basal ornithopod, ankylosaurian) body fossils as well as dinosaurian eggs. We use photogrammetry and 3D imaging to reinterpret the sauropod tracks from Lishui City, which revealed the existence of trackways. The track record from three documented sites in Zhejiang Province includes avian and non-avian theropod, sauropod, ornithopod and pterosaur tracks. Previous work showed that the purported new bird ichnospecies Dongyangornipes sinensis is a synonym of Uhangrichnus chuni, while we here consider Pteraichnus dongyangensis as a nomen dubium. Such “provincial ichnotaxonomy” may mask similarities in the ichnofauna across large regions. In fact, we show that the ichnofauna is similar to that found in the Early Cretaceous elsewhere in China.

© The Palaeontological Association. The collection and dissemination of vertebrate ichnological data is struggling to keep up with techniques that are becoming commonplace in the wider palaeontological field. A standard protocol is required to ensure that data is recorded, presented and archived in a manner that will be useful both to contemporary researchers, and to future generations. Primarily, our aim is to make the 3D capture of ichnological data standard practice, and to provide guidance on how such 3D data can be communicated effectively (both via the literature and other means) and archived openly and in perpetuity. We recommend capture of 3D data, and the presentation of said data in the form of photographs, false-colour images, and interpretive drawings. Raw data (3D models of traces) should always be provided in a form usable by other researchers (i.e. in an open format). If adopted by the field as a whole, the result will be a more robust and uniform literature, supplemented by unparalleled availability of datasets for future workers.

Panel data methodology is one of the most popular tools for quantitative analysis in the field of social sciences, particularly on topics related to economics and business. This technique allows simultaneously dressing individual effects, numerous periods, and in turn, the endogeneity of the model or independent regressors. Despite these advantages, there are several methodological and practical limitations to perform estimations using this tool. There are two types of models that can be estimated with Panel data: Static and Dynamic, the former is the most developed while dynamic models still have some theoretical and practical constraints. This paper focuses precisely on the latter, Dynamic panel data, using an approach that combines theory and praxis, and paying special attention on its applicability on macroeonomic data, specially datasets with a long period of time and a small number of individuals, also called long panels. Resumen La metodología de Datos de Panel es una de las técnicas más usadas para realizar análisis cuantitativos en el ámbito de las ciencias sociales, especialmente en temas relacionados con la economía y los negocios. Su riqueza reside en que esta técnica permite trabajar con varios periodos de tiempo, incorporar los efectos individuales, y a su vez, tratar la endogeneidad. A pesar de estas ventajas, existen diversos obstáculos para su implementación, tanto metodológicos como operativos. Dentro de los tipos de modelos que se pueden estimar con Datos de Panel, los de carácter estáticos han sido los más desarrollados, persistiendo aún carencias teórico-prácticas para los modelos dinámicos. Este artículo pone precisamente su énfasis en estos últimos, aplicando un enfoque que conjuga la teoría y la praxis, y prestando especial atención a su aplicabilidad para datos macroeconómicos, fundamentalmente para paneles que poseen un período de tiempo largo y un número de individuos pequeño.

Many developing countries have defined successful catching-up strategies based on knowledge and capabilities upgrading. However, this is a path dependent country-specific process that may turn more complex in economies based on natural resources (NR). This paper adopts a knowledge-based economy approach to analyze the key dimensions of catching up applied to the Chilean experience. Results allow us to identify development drivers and to derive policy implications that can be generalized to other catching-up economies. The main contribution is to show how openness and some physical production factors become basic determinants of convergence for NR-based countries due to foreign technologies and knowledge absorption opportunities, while national innovation capabilities and the unequal income distribution are still serious weaknesses.

Este artículo analiza el sistema de Ciencia y Tecnología (CyT) de Corea Sur, poniendo atención en la colaboración internacional con la Unión Europea (UE), con el fin de ayudar a comprender el desarrollo económico de Corea, obtener recomendaciones e identificar oportunidades de colaboración para Europa. Para ello, se revisa y analiza información disponible en bases de datos, tratados internacionales de colaboración en CyT entre Corea y la UE, así como antecedentes y estudios previos sobre esta temática. Para tales efectos, el estudio se orienta a analizar la estructura y evolución del sistema coreano de CyT y los principales mecanismos de colaboración con la UE y, a la vez, identificar los principales desafíos y oportunidades para incrementar la actividad científica y tecnológica conjunta Corea-UE. Los resultados obtenidos, junto con reconocer el avance del sistema científico y tecnológico de Corea y las vías seguidas para lograrlo, se evidencia que la colaboración Corea-UE ha sido débil, coexistiendo una gran oportunidad de incrementarla gracias a la coincidencia de estrategias y perspectivas de desarrollo. También es claro que parte importante de la CyT que lleva a cabo Corea es el resultado de la actividad privada y en particular de las empresas multinacionales.ABSTRACTThis study analyses the Science and Technology (S&T) system of South Korea, putting special attention on the international collaboration with European Union (EU) in order to understand the Korean progress based on science, as well as to identify new opportunities from scientific cooperation between those economies. To do this, we analyse secondary information available in international databases, documentation related to international treaties of S&T collaboration of Korea with Europe as well as background and previous studies on the Korean S&T. The purpose of this paper is to analyse the evolution and structure of the Korean S&T system, the mechanisms of collaboration with EU, compared with United States of America, and to identify the main challenges and opportunities in order to increase scientific activities between Korea and EU. Along with the evidence that S&T system of Korea evolved positively, despite the fact that Korea-EU cooperation has been weak, findings also note that there are important ways for future collaborative S&T works due to the coincidence of strategies and development perspectives. It is also clear multinational companies in Korea are nowadays an important source of S&T development.

Venoms can deleteriously affect any physiological system reachable by the bloodstream, including directly interfering with the coagulation cascade. Such coagulopathic toxins may be anticoagulants or procoagulants. Snake venoms are unique in their use of procoagulant toxins for predatory purposes. The boomslang (Dispholidus typus) and the twig snakes (Thelotornis species) are iconic African snakes belonging to the family Colubridae. Both species produce strikingly similar lethal procoagulant pathologies. Despite these similarities, antivenom is only produced for treating bites by D. typus, and the mechanisms of action of both venoms have been understudied. In this study, we investigated the venom of D. typus and T. mossambicanus utilising a range of proteomic and bioactivity approaches, including determining the procoagulant properties of both venoms in relation to the human coagulation pathways. In doing so, we developed a novel procoagulant assay, utilising a Stago STA-R Max analyser, to accurately detect real time clotting in plasma at varying concentrations of venom. This approach was used to assess the clotting capabilities of the two venoms both with and without calcium and phospholipid co-factors. We found that T. mossambicanus produced a significantly stronger coagulation response compared to D. typus. Functional enzyme assays showed that T. mossambicanus also exhibited a higher metalloprotease and phospholipase activity but had a much lower serine protease activity relative to D. typus venom. The neutralising capability of the available boomslang antivenom was also investigated on both species, with it being 11.3 times more effective upon D. typus venom than T. mossambicanus. In addition to being a faster clotting venom, T. mossambicanus was revealed to be a much more complex venom composition than D. typus. This is consistent with patterns seen for other snakes with venom complexity linked to dietary complexity. Consistent with the external morphological differences in head shape between the two species, CT and MRI analyses revealed significant internal structural differences in skull architecture and venom gland anatomy. This study increases our understanding of not only the biodiscovery potential of these medically important species but also increases our knowledge of the pathological relationship between venom and the human coagulation cascade.

Venom systems have evolved on multiple occasions across the animal kingdom, and they can act as key adaptations to protect animals from predators [1]. Consequently, venomous animals serve as models for a rich source of mimicry types, as non-venomous species benefit from reductions in predation risk by mimicking the coloration, body shape, and/or movement of toxic counterparts [2, 3, 4, 5]. The frequent evolution of such deceitful imitations provides notable examples of phenotypic convergence and are often invoked as classic exemplars of evolution by natural selection. Here, we investigate the evolution of fangs, venom, and mimetic relationships in reef fishes from the tribe Nemophini (fangblennies). Comparative morphological analyses reveal that enlarged canine teeth (fangs) originated at the base of the Nemophini radiation and have enabled a micropredatory feeding strategy in non-venomous Plagiotremus spp. Subsequently, the evolution of deep anterior grooves and their coupling to venom secretory tissue provide Meiacanthus spp. with toxic venom that they effectively employ for defense. We find that fangblenny venom contains a number of toxic components that have been independently recruited into other animal venoms, some of which cause toxicity via interactions with opioid receptors, and result in a multifunctional biochemical phenotype that exerts potent hypotensive effects. The evolution of fangblenny venom has seemingly led to phenotypic convergence via the formation of a diverse array of mimetic relationships that provide protective (Batesian mimicry) and predatory (aggressive mimicry) benefits to other fishes [2, 6]. Our results further our understanding of how novel morphological and biochemical adaptations stimulate ecological interactions in the natural world.

In recent decades, the identification of small non-coding RNAs in bacteria has revealed an important regulatory mechanism of gene expression involved in the response to environmental signals and to the control of virulence. In the family Vibrionaceae, which includes several human and animal pathogens, small non-coding RNAs (sRNAs) are closely related to important processes including metabolism, quorum sensing, virulence, and fitness. Studies conducted in silico and experiments using microarrays and high-throughput RNA sequencing have led to the discovery of an unexpected number of sRNAs in Vibrios. The present review discusses the most relevant reports regarding the mechanisms of action of sRNAs and their implications in the virulence of the main human pathogens in the family Vibrionaceae: Vibrio parahaemolyticus, V. vulnificus and V. cholerae.

REGULAR Finalizado FONDECYT-REGULAR FONDECYT Biología 3 FONDECYT

El impulso que en España recibiera la ciencia y la tecnología en los años 80, cuando se aprobó la primera Ley de la Ciencia y el Primer Plan Nacional de Investigación y Desarrollo (I+D),2 no ha seguido un ritmo suficientemente intenso ni constante como para que este tema ocupe un lugar central en la agenda política del país. A pesar de que en las últimas décadas España ha realizado un escalamiento de posiciones en I+D, al compararse con el contexto internacional y con el más reducido ámbito europeo, el sistema español parece haberse quedado más rezagado en su comportamiento tecnológico que al atender a otros elementos de la estructura económica y social del país.

The largest dinosaurian tracks at Lark Quarry, central-western Queensland, Australia, were re-examined using revised analytical protocols that incorporate three-dimensional (3D) structure. Comparisons were made with archival photographs, replica specimens (c. 1977) and the in situ tracks (2013) to account for changes to the track surface. Damage caused both during and after the excavation of the tracks was evident, and in cases where the archival photographs and 1970's replicas strongly differ from the in situ tracks, it is apparent that restoration has modified the original track morphology. Even after accounting for recent damage and alteration, several of the track morphologies obtained from new 3D evaluation models differ considerably from the track outlines that were published in the original description of the site. Compared with the new set of representations, some of the original outlines seem to represent simpler, stylized versions of the tracks. A number of the original outlines are >20% larger than the in situ tracks, while others appear to incorporate cracks as part of the margin of digit impressions. Overall, the best-preserved tracks show blunt digit impressions, reaffirming the idea that the trackmaker was a large ornithopod and supporting a reassignment to cf. Iguanodontipus. The new analysis also reveals the nature of the displacement rims associated with the tracks, and the overprinting of these rims by other ichnites—initially by tool marks (presumably caused by floating vegetation) and then by other dinosaurian tracks (assignable to Wintonopus latomorum). In the context of these observations, we see no evidence for an interaction between the cf. Iguanodontipus trackmaker and the smaller-bodied W. latomorum trackmakers, as neither can be inferred to have been present at the tracksite at, or even close to the same time. Similarly, there is no evidence to support the idea that the approach of the cf. Iguanodontipus trackmaker in some way triggered the movement of the W. latomorum trackmakers. Rather than a snap-shot of dinosaurian ‘stampede’, this study supports the idea that Lark Quarry most likely represents a complex time-averaged assemblage of multiple dinosaurian ichnites, preserved over an extended period of time (hours to days) and bracketed by discrete phases of trackmaker activity and fluctuations in water depth.

MATEM es un proyecto de extensión universitaria. Entre sus objetivos está el mejoramiento de la educación matemática a nivel del ciclo diversificado y, para ello, las universidades estatales trabajan en conjunto con profesores y estudiantes de secundaria. El objetivo de este artículo es mostrar sobre la indagación realizada sobre diversos aspectos del proyecto MATEM, con el fin de evaluar su desarrollo y considerar las recomendaciones para la toma de decisiones. Se resume la percepción de los estudiantes de secundaria inscritos en los cursos Precálculo y Cálculo de MATEM-UNA en el año 2012 y la opinión de los docentes tutores. Se encontró que MATEM es una actividad académica atractiva para los docentes de matemáticas y la población estudiantil de diferentes regiones del país, aunque en ocasiones no se cuente con las condiciones necesarias para desarrollarlo en sus respectivas instituciones. El reconocimiento de un curso universitario, obtener más práctica para la prueba de bachillerato, aumentar sus conocimientos en matemática y prepararse para los cursos universitarios constituyen los aspectos que más motivan a los estudiantes a inscribirse en el proyecto. Al respecto, el desarrollo de habilidades y destrezas de razonamiento resultó el mencionado con mayor frecuencia por los entrevistados. "MATEM" is a university outreach project. Among its objectives is to improve the mathematics education at the high school level and to accomplish it public universities work together with high school´s teachers and students. The study´s aim was to research various aspects of MATEM Project to order to evaluate its development and consider recommendations for making decisions. This paper summarizes the perceptions of high school students enrolled during 2012 in courses Precalculus and Calculus, moreover the opinion of mathematics teachers. The main results were that MATEM is an academic activity attractive for math teachers and student population from different regions of the country, although sometimes are not available the necessary conditions to develop it in their respective institutions, to have passed a university course, get more practice for the standard test at the end of high school, increase their math skills and prepare for college courses were the aspects that motivate students to enroll in the project, however the development of reasoning skills and abilities were more frequently pointed by respondents.

Flavobacterium psychrophilum is an important fish pathogen worldwide that causes cold water disease (CWD) or rainbow trout fry syndrome (RTFS). Phage therapy has been suggested as an alternative method for the control of this pathogen in aquaculture. However, effective use of bacteriophages in disease control requires detailed knowledge about the diversity and dynamics of host susceptibility to phage infection. For this reason, we examined the genetic diversity of 49 F. psychrophilum strains isolated in three different areas (Chile, Denmark, and USA) through direct genome restriction enzyme analysis (DGREA) and their susceptibility to 33 bacteriophages isolated in Chile and Denmark, thus covering large geographical (>12,000 km) and temporal (>60 years) scales of isolation. An additional 40 phage-resistant isolates obtained from culture experiments after exposure to specific phages were examined for changes in phage susceptibility against the 33 phages. The F. psychrophilum and phage populations isolated from Chile and Denmark clustered into geographically distinct groups with respect to DGREA profile and host range, respectively. However, cross infection between Chilean phage isolates and Danish host isolates and vice versa was observed. Development of resistance to certain bacteriophages led to susceptibility to other phages suggesting that “enhanced infection” is potentially an important cost of resistance in F. psychrophilum, possibly contributing to the observed co-existence of phage-sensitive F. psychrophilum strains and lytic phages across local and global scales. Overall, our results showed that despite the identification of local communities of phages and hosts, some key properties determining phage infection patterns seem to be globally distributed.

The Qiaomaigoumen dinosaur tracksite was previously described briefly in 1995 and 2006 based on examination of a single surface (∼200 m2) with five trackways representing two quadrupedal ornithopods (Caririchnium isp.) and three bipedal theropods. While confirming this general description, this study also revealed that two additional sites (Sangyuan I and II) had been found, and that tracks from all three sites had been collected for local institutions. This created the opportunity to describe the ichnofauna more completely, including a variety of theropod morphotypes (cf. Jialingpus isp. and cf. Eubrontes isp.) not previously identified in this area. It is also inferred that the tracksites occur in the Xiguayuan Formation, not in the Jiufotang Formation as previously suggested. This indicates an equivalency with the Jehol Biota and some track elements corresponding generally to Jehol body fossils.

The Lark Quarry dinosaur tracksite has previously been recognized as recording the stampede of a mixed herd of dozens of small theropod and ornithopod dinosaurs. A reexamination of trackway material reveals that the small theropod-type tracks, previously assigned to the ichnotaxon Skartopus, can co-occur within individual trackways of the ornithopod-type tracks assigned to Wintonopus. Moreover, in singular deep tracks where the overall surface outline resembles Skartopus, the base of the track can also resemble Wintonopus. Whereas the Wintonopus holotype may reflect the pedal anatomy of a short-toed or subunguligrade ornithopod trackmaker, the elongate 'toe' impressions typically associated with Skartopus (including the holotype) primarily provide information on digit movement through the sediment and, in many instances, may represent swim traces. The morphological differences between the two ichnotaxa are therefore not taxonomically significant and we formally propose that Skartopus australis should be considered a junior synonym of Wintonopus latomorum. Longitudinal depth profiles through tracks indicate that many are swim traces. The sedimentology and lithology of Lark Quarry further indicates the site represents a time-averaged assemblage formed in a fluvial-dominated floodplain under variable subaqueous conditions, with the parallel orientation of the numerous trackways formed by trackmakers under the influence of downstream current flow. This indicates that the fluvial environment may have been a preferred route for hydrophilic bipedal dinosaurs. We thus do not consider the Lark Quarry dinosaur tracksite to represent a 'stampede.' Instead, the tracksite may represent part of a riverine setting, where the water was shallow, in which small dinosaurs swam and/or waded.

Pathogenic V. parahaemolyticus strains are able to adapt from environmental to laboratory isolation conditions that simulate some conditions upon infection in humans. To explore this adaptation, we determined the differential expression by RNAseq when growing in conditions for clinical isolation “I” (LB, NaCl 0.9% and 37 oC plus bile acid) referred to those in their natural environment “E” (LB, NaCl 3% and 12 oC). Analysis or the reads obtained after sequencing the RNA showed that 77% of the annotated genome was expressed in isolation (3841 genes) condition and 84% (4143 genes) in environmental condition. Our transcriptome analysis revealed that among the 50 genes expressed in higher amount in each conditions, 21 were differentially expressed; 4 were downregulated and 17 upregulated in isolation condition; 14 corresponded to coding sequences (CDS), 5 to small-RNA and 3 to tRNA.

Bacterial genomes evolve through two different mechanisms: 1) changes in or occasional loss of ancestral genes, which preserve the founder clonal genealogy or frame, and 2) sporadic gains of new genes via horizontal gene transfer, which introduces DNA with a different genealogy or clonal frame. Evolution has led to the emergence of a pathogenic strain pandemic of Vibrio parahaemolyticus, which has propagated globally, causing large outbreaks of seafood-associated diarrhea. The low sequence diversity of the pathogenic strain of Vibrio parahaemolyticus genome provides a model that can reveal evolutionary mechanisms that are hidden in bacteria with a greater diversity. Here, we assess the clonal genealogy of the genome components of Vibrio parahaemolyticus and identify recombinant segments in 31 isolates obtained worldwide. By comparing whole genomes using a procedure that accounts for at least 98% of the reads obtained from any isolate after high throughput sequencing, we determined that the fraction of the whole genome retaining the founder clonal frame varied from 96.7%-100% of the accountable reads. The fraction in chromosomes with other genealogies varied from 0%-3.3% and in extra-chromosomal elements from 0%-4.2%, with the relative impact of mutation and recombination varying greatly between isolates. The likely causes for this variation are proposed.

Summary Seafood consumption-related diarrhoea increased drastically in Chile when the pandemic strain of Vibrio parahaemolyticus serotype O3:K6 reached Region de Los Lagos, where most of Chile's seafood is produced. Outbreaks peaked in 2005 with 3725 clinical cases in this region and gradually decreased to fewer than 10 cases in 2010 and 2011. We show here that the pandemic strain concurrently vanished from mussels; we also report further environmental data. Integration of the 2010/2011 data with those obtained since 2004 suggests that after its arrival in southern Chile, the pandemic strain grew in mussels, likely facilitated by a minor rise in surface seawater temperature and by warming of the mussels in the intertidal region due to frequent sunny days. However, since these environmental parameters probably equally affected the pandemic strain and more than 30 V. parahaemolyticus DNA restriction clusters that inhabit local shellfish, a selective effect of bacteriophages is proposed. Lytic bacteriophage VP93 may have favoured the growth of the pandemic strain versus similar phage-sensitive strains, as shown here in a particular case. However, the pandemic strain's decline may have been promoted by temperate phage VP58.5, which kills the pandemic strain and increases the UV sensitivity of lysogenized phage-resistant cells.

This work was partially supported by Grant INNOVA 07CN13PPT-09 of CORFO, Chile, and by grants from the Directorate for Food, Fisheries and Agri Business and the Danish Natural Sciences Research Council to M.M.

Multivariate analysis is used to differentiate shape variations between ichnites of theropod and ornithopod dinosaurs. Tracks of an alleged theropod cf. Tyrannosauropus from the mid-Cretaceous (late Albian-Cenomanian) Winton Formation of Lark Quarry, central-western Queensland, Australia were examined and foot shape ratios calculated. Multivariate analysis of these shape variables indicates this track-maker was an ornithopod dinosaur. A strong morphological similarity exists between the Lark Quarry ichnites and those of the iguanodontian ichnotaxon Amblydactylus gethingi. Considering the grade of ornithopod this ichnogenus is thought to represent (a non-hadrosaurid styracosternan) and the age and geography of Lark Quarry, we suggest that the track-maker may have been a dinosaur similar to Muttaburrasaurus langdoni. (C) 2010 Elsevier Ltd. All rights reserved.

The dynamics of dissemination of the environmental human pathogen Vibrio parahaemolyticus are uncertain. The O3:K6 clone was restricted to Asia until its detection along the Peruvian coasts and in northern Chile in 1997 in phase with the arrival of El Nino waters. A subsequent emergence of O3:K6 strains was detected in austral Chile in 2004. The origin of these 1997 and 2004 population radiations has not yet been conclusively determined. Multiple loci VNTR analysis using seven polymorphic loci was carried out with a number of representative strains from Asia, Peru and Chile to determine their genetic characteristics and population structure. Asian and Chilean subpopulations were the most genetically distant groups with an intermediate subpopulation in Peru. Population structure inferred from a minimum-spanning tree and Bayesian analysis divided the populations into two genetically distinct groups, consistent with the epidemic dynamics of the O3:K6 clone in South America. One group comprised strains from the original Asiatic population and strains arriving in Peru and Chile in 1997. The second group included the remaining Peruvian Strains and Chilean strains obtained from Puerto Montt in 2004. The analysis of the arrival of the O3:K6 clone at the Pacific coasts of South America has provided novel insights linking the origin of the invasion in 1997 to Asian populations and describing the successful establishment of the O3:K6 populations, first in Peru and subsequently in the South of Chile owing to a possible radiation of Peruvian populations.

Roberto Bastias acknowledges scholarship from Programa MECE Educacion Superior, proyecto UCH 0407. This work was partially supported by Grant FONDECYT 1076054.