Efecto de los parámetros cinéticos de escalamiento del cultivo de Haematococcus pluvialis en fotobiorreactores para producir astaxantina

Haematococcus pluvialis is a microalga of biotechnological interest due to its ability to produce astaxanthin, a carotenoid that is used as a pigment and a bioactive compound. It has applications in the pharmaceutical, cosmetic, nutraceutical, food, and aquaculture industries. This carotenoid is obtained when the microalgae is subjected to stress conditions such as light intensity, light color, nutrient deficiency, and salinity, and involves the use of photobioreactors (PBR). For this reason, this article is intended to show the type of PBR that has been used in its scaling and the related kinetic parameters that influence the performance of the process. PBRs facilitate the adjustment and control of the cultivation conditions, both in the green phase and in the red phase. Likewise, the use of the kinetic scaling parameters allows evaluating the process, thus, establishing the conditions that must be adjusted, to improve the cultivation of the microalgae and obtaining astaxanthin. The kinetic scaling parameters reviewed were biomass (cel/mL), biomass productivity (g/Lday), specific growth rate (µ/day), doubling time (day), astaxanthin content (mg/g) and its productivity. Thus, the technological feasibility of photobioreactors for the scaling of microalgae to produce astaxanthin is demonstrated. The most commonly used PBRs are tubular and cylindrical because they have a greater illumination surface and efficiency in light distribution, and because they report higher astaxanthin productivity; its downside may be the costs for their cleaning.El Haematococcus pluvialis es una microalga de interés biotecnológico por su capacidad para producir astaxantina, un carotenoide que tiene uso como pigmento y compuesto bioactivo, con aplicación en la industria farmacéutica, cosmética, nutracéutica, alimenticia y la acuacultura. Este carotenoide se obtiene cuando la microalga es sometida a condiciones de estrés como intensidad de luz, color de luz, deficiencia de nutrientes y salinidad, e involucra el uso de fotobiorreactores (fbr). Por esto, este artículo busca conocer el tipo de fbr que se ha utilizado en su escalamiento y los parámetros cinéticos relacionados que influyen en el rendimiento del proceso. Los fbr facilitan el ajuste y control de las condiciones de cultivo, tanto en la fase verde como en la fase roja; de igual manera, el uso de los parámetros cinéticos de escalamiento permiten evaluar el proceso y así establecer las condiciones que deben ajustarse, para mejorar el cultivo de la microalga y la obtención de astaxantina. Los parámetros cinéticos de escalamiento revisados fueron la biomasa (cel./mL), la productividad de biomasa (g/Ldía), la velocidad específica de crecimiento (µ/día), el tiempo de duplicación (día), el contenido de astaxantina (mg/g) y su productividad. Se demuestra así la factibilidad tecnológica de los fotobiorreactores para el escalamiento de la microalga para producir astaxantina. Los fbr más usados son los de forma tubular y cilíndrica por tener una superficie mayor de iluminación y eficiencia en la distribución de la luz, y por reportar mayor productividad de astaxantina; su desventaja pueden ser los costos de limpieza

A simple mathematical model that describes the growth of the area and the number of total and viable cells in yeast colonies

We propose a model, based on the Gompertz equation, to describe the growth of yeasts colonies on agar medium. This model presents several advantages: (i) one equation describes the colony growth, which previously needed two separate ones (linear increase of radius and of the squared radius); (ii) a similar equation can be applied to total and viable cells, colony area or colony radius, because the number of total cells in mature colonies is proportional to their area; and (iii) its parameters estimate the cell yield, the cell concentration that triggers growth limitation and the effect of this limitation on the specific growth rate. To elaborate the model, area, total and viable cells of 600 colonies of Saccharomyces cerevisiae, Debaryomyces fabryi, Zygosaccharomyces rouxii and Rhodotorula glutinis have been measured. With low inocula, viable cells showed an initial short exponential phase when colonies were not visible. This phase was shortened with higher inocula. In visible or mature colonies, cell growth displayed Gompertz-type kinetics. It was concluded that the cells growth in colonies is similar to liquid cultures only during the first hours, the rest of the time they grow, with near-zero specific growth rates, at least for 3 weeks

Desafío tecnológico: herramienta para trabajar y evaluar las competencias básicas y generales en los estudios de grado de la E.T.S.I. de Telecomunicación

This work presents the evolution of the five editions of the educational activity named “Technological Challenge” specially focused on the students at “Escuela Técnica Superior de Ingeniería de Telecomunicación” (ETSIT), but open to all students of the “Universidad de Málaga” (UMA). This initiative has been developed in the context of the educational innovation project PIE17-021 funded by UMA. The “Technological Challenge” consists on the formulation of specific real problems, which students must face in a competitive regime. This activity allows the reinforcement and evaluation of basic and general competences reached by the graduate students in the ETSIT. After nearly five years, this paper describes the evaluation of the results, regarding interest and participation of the students in the “Technology Challenge” along with the basic and general competences reached by the students.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. PIE17-02

Old Age Prejudice in Mexican University Students: Comparisons by Gender

The goal of the present research was to compare the profiles of old age prejudice in male and female students from the area of physical activity. The study was conducted from January to October 2016. Participants were recruited from different semesters of the Physical Education and Human Motricity bachelor’s degrees offered at the Faculty of Physical Culture Sciences of the Autonomous University of Chihuahua, Mexico. The sample was obtained through convenience sampling, and included 1652 participants; 828 women and 824 men, mean age was 20.51 ± 1.83 years 20.90 ± 2.03 years respectively. The approach of the study was quantitative with a descriptive survey-like design. All participants completed the Questionnaire on Negative Stereotypes towards Old Age. Results from the Multivariate Analyses of Variance, and the follow-up Univariate Analyses of Variance, show that men report greater levels of prejudice towards old age on the sociomotivational (F = 31.657, p<.001) and character-personality (F = 15.789, p<.001) factors. No differences were found on the health factor (i.e., mental and physical). These results suggest that when designing any type of intervention in which the purpose isto improve the perception of young people towards the elderly, the variable gender should be considered. Future research should replicate these findings in larger samples

Neutrophils instruct homeostatic and pathological states in naive tissues

Immune protection relies on the capacity of neutrophils to infiltrate challenged tissues. Naive tissues, in contrast, are believed to remain free of these cells and protected from their toxic cargo. Here, we show that neutrophils are endowed with the capacity to infiltrate multiple tissues in the steady-state, a process that follows tissue-specific dynamics. By focusing in two particular tissues, the intestine and the lungs, we find that neutrophils infiltrating the intestine are engulfed by resident macrophages, resulting in repression of Il23 transcription, reduced G-CSF in plasma, and reinforced activity of distant bone marrow niches. In contrast, diurnal accumulation of neutrophils within the pulmonary vasculature influenced circadian transcription in the lungs. Neutrophil-influenced transcripts in this organ were associated with carcinogenesis and migration. Consistently, we found that neutrophils dictated the diurnal patterns of lung invasion by melanoma cells. Homeostatic infiltration of tissues unveils a facet of neutrophil biology that supports organ function, but can also instigate pathological states.S

Ciencias de la Biología y Agronomía

Este volumen I contiene 17 capítulos arbitrados que se ocupan de estos asuntos en Tópicos Selectos de Ciencias de la Biología y Agronomía, elegidos de entre las contribuciones, reunimos algunos investigadores y estudiantes. Se presenta un Estudio Comparativo de los Recursos Hidrológico-Forestales de la Microcuenca de la Laguna de Epatlan, Pue. (1993 a 2014); la Situación Actual de la Mancha de Asfalto en Maíz (Zea mays L.) en los Municipios de Jiquipilas y Ocozocoautla, Chiapas, México; las poblaciones sobresalientes de maíz de la raza Zapalote Chico, en la Región Istmeña de Oaxaca; Se indica el índice de área foliar de cultivo de Chile Poblano mediante dos métodos en condiciones protegidas; Esquivel, Urzúa y Ramírez exploran el efecto de la biofertilización con Azospirillum en el crecimiento y producción de Jitomate; esbozan su artículo sobre la determinación del nivel de Heterosis en híbridos de Maíz para la Comarca Lagunera; una investigación sobre la estabilización de semilla de Solanum lycopersicum durante el almacenamiento y estimulación de la germinación; acotan sobre el CTAB como una nueva opción para la detección de Huanglongbing en cítricos, plantean su evaluación sobre el aluminio y cómo afecta la vida de florero de Heliconia psittacorum; indican sobre el impacto del H-564C, como un híbrido de maíz con alta calidad de proteina para el trópico húmedo de México; presetan su investigación sobre la producción de Piña Cayena Lisa y MD2 (Ananas comosus L.) en condiciones de Loma Bonita, en Oaxaca; acotan sobre el efecto de coberteras como control biológico por conservación contra áfidos en Nogal Pecanero; esbozan sobre la caracterización de cuatro genotipos de Frijol Negro en Martínez de la Torre, Veracruz, México; presentan una caracterización hidroecológica de la microcuenca de Arroyo Prieto, Yuriría, Gto., y alternativas para su restauración ambiental; presentan su investigación sobre el efecto del hongo Beauveria bassiana sobre solubilización de fosfatos y la disponibilidad de fósforo en el suelo; plantean su investigación sobre la Germinación y regeneración in vitro de Epidendrum falcatum LINDL; esbozan su artículo sobre genotipos de frijol negro y su tolerancia a sequía terminal en Veracruz, México

Making Waves : Collaboration in the time of SARS-CoV-2-rapid development of an international co-operation and wastewater surveillance database to support public health decision-making

The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE "SARS-CoV-2 in sewage" database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice. (C) 2021 Elsevier Ltd. All rights reserved.Peer reviewe

TWIST1 Is Expressed in Colorectal Carcinomas and Predicts Patient Survival

TWIST1 is a transcription factor that belongs to the family of basic helix-loop-helix proteins involved in epithelial-to-mesenchymal transition and invasion processes. The TWIST1 protein possesses oncogenic, drug-resistant, angiogenic and invasive properties, and has been related with several human tumors and other pathologies. Colorectal cancer is one of the tumors in which TWIST1 is over-expressed, but its involvement in the clinical outcome of the disease is still unclear. We tested, by RT-PCR, the expression levels of TWIST1 in normal and tumor paired-sample tissues from a series of 151 colorectal cancer patients, in order to investigate its prognostic value as a tumor marker. TWIST1 expression was restricted to tumor tissues (86.1%) and correlated with lymph node metastasis (LNM). Adjusted analysis showed that the expression levels of TWIST1 correlated with overall survival (OS) and disease-free survival (DFS). Importantly, TWIST1 expression levels predicted OS specifically at stages I and II. Moreover, patients with stage II tumors and high TWIST1 levels showed even shorter survival than patients with stage III tumors. These results suggest that TWIST1 expression levels could be a tumor indicator in stage II patients and help select patients at greater risk of poor prognosis who might benefit from adjuvant chemotherapy

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives