Aplicación del modelo gravitacional al impacto del gobierno corporativo en las fusiones y adquisiciones en Latinoamérica

En el presente estudio se analiza si la actividad de fusiones y adquisiciones (M&A) transnacionales está influenciada por los estándares de gobierno corporativo de los países. Para lograrlo, se recurre al modelo gravitacional. Se toma la actividad proveniente de países de la OECD y dirigida hacia seis países latinoamericanos y, como medida de gobierno corporativo a nivel país, se usan los indicadores de Kaufmann, entre otros. Se encontró que el modelo gravitacional es explicativo del fenómeno y que a mayor nivel de gobierno corporativo en el país de origen y en el país de destino, mayor es la actividad de M&A.In this study we analyze whether transnational mergers and acquisitions (M&As) are influenced by country level corporate governance standards. For this purpose, we use a gravity model. Additionally, this study focuses only on the M&As flows from the OECD countries towards Latinamerican economies, and we use the Kaufmann indicators as measures of country level corporate governance, among others. We find evidence that the gravity model is explicative of the M&As flows, and that the higher the level of corporate governance at both origin and destination countries, the greater the M&As activity

Maize nutrient composition and the influence of xylanase addition

Altres ajuts SENESCYT CZ02-000816-2018This study assessed differences in nutrient composition, physical characteristics, and xylo-oligosaccharide content with or without xylanase treatment by maize genotype and the grain position on the cob. Ten cobs each from sixteen maize varieties sowed in the same field were collected and classified considering the grain's position on the cob (basal vs apical). The majority of physicochemical characteristics were influenced by an interaction between genetic background and grain position (P < 0.05); however, moisture, crude protein, starch, ash and soluble arabinose:xylose ratio differed between maize varieties and grain on cob position, without interaction. Xylanase addition increased the concentration of soluble compounds and xylotriose content in the aqueous phase following incubation in vitro (P < 0.05) and in the case of xylotriose the amounts released varied with grain position and variety. In conclusion, maize genotype and grain position on the cob significantly influenced chemical composition and oligosaccharide content when treated with xylanase, which may contribute to nutrient variability between maize samples

Informing trait-based ecology by assessing remotely sensed functional diversity across a broad tropical temperature gradient

Spatially continuous data on functional diversity will improve our ability to predict global change impacts on ecosystem properties. We applied methods that combine imaging spectroscopy and foliar traits to estimate remotelysensed functional diversity in tropical forests across an Amazon-to-Andes elevation gradient (215 to 3537 m). We evaluated the scale dependency of community assembly processes and examined whether tropical forest productivitycould be predicted by remotely sensed functional diversity. Functional richness of the community decreased withincreasing elevation. Scale-dependent signals of trait convergence, consistent with environmental filtering, play animportant role in explaining the range of trait variation within each site and along elevation. Single- and multitraitremotely sensed measures of functional diversity were important predictors of variation in rates of net and grossprimary productivity. Our findings highlight the potential of remotely sensed functional diversity to inform trait-based ecology and trait diversity-ecosystem function linkages in hyperdiverse tropical forests.Fil: Durán, Sandra M.. University of Arizona; Estados UnidosFil: Martin, Roberta E.. Arizona State University; Estados UnidosFil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Maitner, Brian S.. Arizona State University; Estados UnidosFil: Malhi, Yadvinder. University of Oxford; Reino UnidoFil: Salinas, Norma. University of Oxford; Reino Unido. Pontificia Universidad Católica de Perú; PerúFil: Shenkin, Alexander. University of Oxford; Reino UnidoFil: Silman, Miles R.. Wake Forest University; Estados UnidosFil: Wieczynski, Daniel J.. University of Oxford; Reino UnidoFil: Asner, Gregory P.. Arizona State University; Estados UnidosFil: Bentley, Lisa Patrick. Sonoma State University; Estados UnidosFil: Savage, Van M.. University of California; Estados UnidosFil: Enquist, Brian J.. Arizona State University; Estados Unido

Conversion of the Mycotoxin Patulin to the Less Toxic Desoxypatulinic Acid by the Biocontrol Yeast Rhodosporidium kratochvilovae Strain LS11

Se describe en este artículo el descubrimiento de la degradación de la micotoxina patulina por una levaduraThe infection of stored apples by the fungus Penicillium expansum causes the contamination of fruits and fruit-derived products with the mycotoxin patulin, which is a major issue in food safety. Fungal attack can be prevented by beneficial microorganisms, so-called biocontrol agents. Previous time-course thin layer chromatography analyses showed that the aerobic incubation of patulin with the biocontrol yeast Rhodosporidium kratochvilovae strain LS11 leads to the disappearance of the mycotoxin spot and the parallel emergence of two new spots, one of which disappears over time. In this work, we analyzed the biodegradation of patulin effected by LS11 through HPLC. The more stable of the two compounds was purified and characterized by nuclear magnetic resonance as desoxypatulinic acid, whose formation was also quantitated in patulin degradation experiments. After R. kratochvilovae LS11 had been incubated in the presence of 13C-labeled patulin, label was traced to desoxypatulinic acid, thus proving that this compound derives from the metabolization of patulin by the yeast. Desoxypatulinic acid was much less toxic than patulin to human lymphocytes and, in contrast to patulin, did not react in vitro with the thiol-bearing tripeptide glutathione. The lower toxicity of desoxypatulinic acid is proposed to be a consequence of the hydrolysis of the lactone ring and the loss of functional groups that react with thiol groups. The formation of desoxypatulinic acid from patulin represents a novel biodegradation pathway that is also a detoxification process

N7-methylguanosine methylation of tRNAs regulates survival to stress in cancer

Tumour progression and therapy tolerance are highly regulated and complex processes largely dependent on the plasticity of cancer cells and their capacity to respond to stress. The higher plasticity of cancer cells highlights the need for identifying targetable molecular pathways that challenge cancer cell survival. Here, we show that

The bien r package: A tool to access the Botanical Information and Ecology Network (BIEN) database

There is an urgent need for largeâ scale botanical data to improve our understanding of community assembly, coexistence, biogeography, evolution, and many other fundamental biological processes. Understanding these processes is critical for predicting and handling humanâ biodiversity interactions and global change dynamics such as food and energy security, ecosystem services, climate change, and species invasions.The Botanical Information and Ecology Network (BIEN) database comprises an unprecedented wealth of cleaned and standardised botanical data, containing roughly 81 million occurrence records from c. 375,000 species, c. 915,000 trait observations across 28 traits from c. 93,000 species, and coâ occurrence records from 110,000 ecological plots globally, as well as 100,000 range maps and 100 replicated phylogenies (each containing 81,274 species) for New World species. Here, we describe an r package that provides easy access to these data.The bien r package allows users to access the multiple types of data in the BIEN database. Functions in this package query the BIEN database by turning user inputs into optimised PostgreSQL functions. Function names follow a convention designed to make it easy to understand what each function does. We have also developed a protocol for providing customised citations and herbarium acknowledgements for data downloaded through the bien r package.The development of the BIEN database represents a significant achievement in biological data integration, cleaning and standardization. Likewise, the bien r package represents an important tool for open science that makes the BIEN database freely and easily accessible to everyone.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142458/1/mee312861_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142458/2/mee312861.pd

Biofabrication of functional protein nanoparticles through simple His-tag engineering

Altres ajuts: Acord transformatiu CRUE-CSICWe have developed a simple, robust, and fully transversal approach for thea-la-cartefabrication of functional multimeric nanoparticles with potential biomedical applications, validated here by a set of diverse and unrelated polypeptides. The proposed concept is based on the controlled coordination between Znions and His residues in His-tagged proteins. This approach results in a spontaneous and reproducible protein assembly as nanoscale oligomers that keep the original functionalities of the protein building blocks. The assembly of these materials is not linked to particular polypeptide features, and it is based on an environmentally friendly and sustainable approach. The resulting nanoparticles, with dimensions ranging between 10 and 15 nm, are regular in size, are architecturally stable, are fully functional, and serve as intermediates in a more complex assembly process, resulting in the formation of microscale protein materials. Since most of the recombinant proteins produced by biochemical and biotechnological industries and intended for biomedical research are His-tagged, the green biofabrication procedure proposed here can be straightforwardly applied to a huge spectrum of protein species for their conversion into their respective nanostructured formats

Toxicidad hematológica asociada al tratamiento con sulfonamidas y pirimetamina en pacientes VIH positivos y toxoplasmosis cerebral en un hospital de tercer nivel en Colombia

Objective.&nbsp;To determine the frequency of hematologic adverse effects associated with treatment for cerebral toxoplasmosis in HIV / AIDS patients. Design: Retrospective case series. Location: University Hospital Hernando Moncaleano Perdomo (HMP), Neiva, Colombia. Population.&nbsp;Patients with cerebral toxoplasmosis and HIV / AIDS treated at the infection service unit between 2006 and 2009. Población.&nbsp;Pacientes con toxoplasmosis cerebral y VIH/SIDA atendidos en el servicio de infectología entre 2006-2009. Results.&nbsp;51 patients were evaluated during the study period. 40 (78%) were men. The average age was 33 years. 25 patients had cerebral toxoplasmosis as the first marker of HIV infection. 60.7% of cases had hematologic toxicity. 42% of patients had anemia before treatment. The peak onset of bone marrow toxicity was the sixth day of the start of treatment schedule. The anti-toxoplasma scheme that was most commonly associated with myelotoxicity was the combination of pyrimethamine/sulfadoxine, trimethoprim-sulfamethoxazole and clindamycin in 48% of cases.&nbsp;Objetivo.&nbsp;Determinar la frecuencia efectos adversos hematológicos asociados al tratamiento para toxoplasmosis cerebral en pacientes VIH/SIDA. Diseño.&nbsp;Serie de casos retrospectiva. Lugar.&nbsp;Hospital Universitario Hernando Moncaleano Perdomo (HMP), Neiva- Colombia. Población.&nbsp;Pacientes con toxoplasmosis cerebral y VIH/SIDA atendidos en el servicio de Infectología entre 2006-2009. Resultados.&nbsp;51 pacientes fueron evaluados durante el periodo de estudio. 40 (78%) fueron hombres. El promedio de edad fue 33 años. 25 pacientes presentaban toxoplasmosis cerebral como primer marcador de Infección VIH. El 60,7% de los casos presentaron toxicidad hematológica. 42% de los pacientes presentaron anemia previa al tratamiento. El pico de aparición de toxicidad medular fue al sexto día de inicio del esquema de tratamiento. El esquema antitoxoplasma que más comúnmente fue asociado a mielotoxicidad fue la combinación de pirimetamina/sulfadoxina, trimetoprimsulfametoxazol y clindamicina en 48% de los casos

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Neuroblastoma RAS viral oncogene homolog (N-RAS) deficiency aggravates liver injury and fibrosis.

Progressive hepatic damage and fibrosis are major features of chronic liver diseases of different etiology, yet the underlying molecular mechanisms remain to be fully defined. N-RAS, a member of the RAS family of small guanine nucleotide-binding proteins also encompassing the highly homologous H-RAS and K-RAS isoforms, was previously reported to modulate cell death and renal fibrosis; however, its role in liver damage and fibrogenesis remains unknown. Here, we approached this question by using N-RAS deficient (N-RAS-/-) mice and two experimental models of liver injury and fibrosis, namely carbon tetrachloride (CCl4) intoxication and bile duct ligation (BDL). In wild-type (N-RAS+/+) mice both hepatotoxic procedures augmented N-RAS expression in the liver. Compared to N-RAS+/+ counterparts, N-RAS-/- mice subjected to either CCl4 or BDL showed exacerbated liver injury and fibrosis, which was associated with enhanced hepatic stellate cell (HSC) activation and leukocyte infiltration in the damaged liver. At the molecular level, after CCl4 or BDL, N-RAS-/- livers exhibited augmented expression of necroptotic death markers along with JNK1/2 hyperactivation. In line with this, N-RAS ablation in a human hepatocytic cell line resulted in enhanced activation of JNK and necroptosis mediators in response to cell death stimuli. Of note, loss of hepatic N-RAS expression was characteristic of chronic liver disease patients with fibrosis. Collectively, our study unveils a novel role for N-RAS as a negative controller of the progression of liver injury and fibrogenesis, by critically downregulating signaling pathways leading to hepatocyte necroptosis. Furthermore, it suggests that N-RAS may be of potential clinical value as prognostic biomarker of progressive fibrotic liver damage, or as a novel therapeutic target for the treatment of chronic liver disease