Nitrate and Inhibition of Ruminal Methanogenesis : Microbial Ecology, Obstacles, and Opportunities for Lowering Methane Emissions from Ruminant Livestock

Acknowledgments CY was supported by a scholarship from the China Scholarship Council. IC was supported by the SRUC International Engagement Strategy Fund. The nitrate project was funded by EBLEX, a Division of the Agriculture and Horticulture Development Board. RINH and SRUC are funded by the Rural and Environment Science and Analytical Services Division (RESAS) of the Scottish Government.Peer reviewedPublisher PD

Ruminant nutrition and function: understanding methane mitigation routes and impacts

Methane is a potent greenhouse gas with a global warming potential 21 times that of carbon dioxide. Globally, ruminants are the main anthropogenic contributors to methane release to the atmosphere. Methane is produced in the gastrointestinal tract of ruminants, mostly within the rumen by methanogenic archaea. However, methane production represents a loss of 2 to 12% of dietary gross energy for the animal, which could otherwise be available for growth or milk production. Therefore, mitigation of methane production by ruminants could produce both economic and environmental benefits, with more sustainable and energy efficient livestock, and offering a promising way of slowing global warming. Despite extensive research undertaken to find ways of reducing methane emissions from ruminants, progress has been relatively limited. Furthermore, there is still a lack of studies linking rumen microbiology and ruminant nutrition and production. The central purpose of this research was to investigate feed additives to reduce methane emissions and to understand associated changes that occur in the rumen microbiota. For the first experiment (Chapter 2), biochar was evaluated as an antimethanogenic compound for beef cattle. The in vitro gas production technique was used to study the effects of biochar on rumen fermentation and methane production. Overall, methane production was reduced by 5% by the addition of biochar compounds (10 g/kg of substrate). The observed reduction in methane produced was not associated with a change in volatile fatty acid profile suggesting biochar primarily inhibited fermentation. Ammonia concentration was significantly reduced with biochar inclusion. Because different biochars had different effects on methane production, further investigation of relationships between the physicochemical properties of biochars and antimethanogenic effects are necessary. However, due to the small reduction in methane production recorded, research with biochar was discontinued. Encapsulated nitrate was then explored as an antimethanogenic additive and as an alternative non-protein nitrogen source to urea (Chapter 3). The effect of using encapsulated nitrate as a replacement for urea or dietary protein, plus the addition of inorganic sulphur, on enteric methane emissions, nutrient digestibility, nitrogen utilization and microbial protein synthesis from crossbred beef steers were studied. In addition, nitrate toxicity and eating behaviour were investigated. The inclusion of encapsulated nitrate reduced methane production compared to urea and a true protein source, with no adverse effects on rumen fermentation or nitrogen metabolism and no effects with the inclusion of elemental sulphur. The level of addition of encapsulated nitrate (14.3 g nitrate /kg DM) and the time of adaptation chosen for this study (14 days) were adequate to avoid nitrate toxicity. Finally, the effects of adding nitrate inclusion to different basal diets on rumen microbial populations and relationships of these populations with methane production were investigated (Chapter 4). The V4 hypervariable regions of the bacterial and archaea 16S rRNA genes were amplified and sequenced. Effects on microbial population induced by nitrate were dependant on the basal diet but nitrate altered specific archaeal and bacterial OTUs consistently between studies. A direct and strong correlation between some archaea taxonomic groups and OTUs with methane production was observed

Gestión directiva y clima organizacional en una institución educativa inicial, El Porvenir-Trujillo, 2023

Esta investigación buscó describir la problemática existente en un centro educativo de Trujillo; con la finalidad de determinar la relación entre la gestión directiva y el clima organizacional en una institución educativa nivel inicial, El Porvenir-Trujillo, 2023. Para ello, la metodología empleada fue de tipo básica, no experimental transversal y alcance correlacional. La población estuvo conformada por la plana docente y jerárquica de la institución y la muestra constituida por 25 trabajadores de la institución educativa en cuestión. El instrumento de recogida de datos utilizado en este estudio fue un cuestionario aplicado mediante una encuesta. La normalidad de los datos se evaluó a través de la prueba de Shapiro-Wilk, la misma que confirmó la no normalidad en la distribución de los datos, por ello, se recurrió a la prueba de correlación de Spearman. Los resultados de la investigación revelaron una relación directa, fuerte y significativa, con un coeficiente de correlación de Spearman de 0,854 y un nivel de significancia menor a 0,05. Concluyendo que existe relación entre la gestión directiva y el clima organizacional en una institución educativa inicial, El Porvenir-Trujillo

Marcadores de velocidad de envejecimiento y predictores de longevidad

El envejecimiento puede definirse como un proceso universal en el que se produce toda una serie de cambios biológicos, y que se caracteriza por una disminución progresiva y generalizada de la función del organismo y por una menor capacidad para restaurar la homeostasis. Además, el proceso de envejecimiento presenta una gran heterogeneidad, de manera que los individuos de una población, pertenecientes a una misma especie y con idéntica edad cronológica, pueden hacer este proceso a diferente velocidad. Este hecho ha llevado a desarrollar el concepto de edad biológica, para cuyo establecimiento es necesario determinar una serie de variables que cambian con la edad y que están relacionadas con una muerte prematura. Esta edad biológica es más adecuada que la cronológica como indicador del estado de salud, el rendimiento físico y mental, así como de la velocidad a la que está envejeciendo un individuo..

Global patterns of functional trait variation along aridity gradients in bats

Aim Our understanding of the biological strategies employed by species to cope with challenges posed by aridity is still limited. Despite being sensitive to water loss, bats successfully inhabit a wide range of arid lands. We here investigated how functional traits of bat assemblages vary along the global aridity gradient to identify traits that favour their persistence in arid environments. Location Global. Time period Contemporary. Major taxa studied Bats. Methods We mapped the assemblage-level averages of four key bat traits describing wing morphology, echolocation and body size, based on a grid of 100-km resolution and a pool of 915 bat species, and modelled them against aridity values. To support our results, we conducted analyses also at the species level to control for phylogenetic autocorrelation. Results At the assemblage level, we detected a rise in values of aspect ratio, wing loading and forearm length, and a decrease in echolocation frequency with increasing aridity. These patterns were consistent with trends detected at the species level for all traits. Main conclusions Our findings show that trait variation in bats is associated with the aridity gradient and suggest that greater mobility and larger body size are advantageous features in arid environments. Greater mobility favours bats' ability to track patchy and temporary resources, while the reduced surface-to-volume ratio associated with a larger body size is likely to reduce water stress by limiting cutaneous evaporation. These findings highlight the importance of extending attention from species-specific adaptations to broad scale and multispecies variation in traits when investigating the ability of species to withstand arid conditions.Peer reviewe

Effect of Supervised Resistance Training on Arm Volume, Quality of Life and Physical Perfomance Among Women at High Risk for Breast Cancer-Related Lymphedema: A Study Protocol for a Randomized Controlled Trial (STRONG-B)

The study is funded by ANID+FONDEF/XVII Concurso Nacional de Proyectos de Investigacion y Desarrollo en Salud, Fonis (SA20I0060).Objectives: To determine the preventive effects of supervised resistance training on arms volume, quality of life, physical performance, and handgrip strength in Chilean women at high risk for breast cancer-related lymphedema (BCRL) undergoing chemotherapy. Design: Randomized control trial. Participants: One hundred and six women at high risk for breast cancer-related lymphedema aged 18 to 70 years. Interventions: Participants will be randomized into two groups: [a] intervention, who will receive 12 weeks of supervised resistance training (STRONG-B) during adjuvant chemotherapy; and [b] control, who will receive education to promote lymphatic and venous return, maintain range of motion, and promote physical activity. Main Outcome Measures: The primary outcome will be arms volume measured with an optoelectric device (perometer NT1000). Secondary outcomes will be quality of life, handgrip strength, and physical performance. Primary and secondary outcomes will be measured at baseline, just after the intervention, and 3 and 6 months after. Statistical analysis will be performed following intention-to-treat and per-protocol approaches. The treatment effect will be calculated using linear mixed models. Discussion: The STRONG-B will be a tailored supervised resistance training that attempts to prevent or mitigate BCRL in a population that, due to both intrinsic and extrinsic factors, will commonly suffer from BCRL.ANID+FONDEF/XVII Concurso Nacional de Proyectos de Investigacion y Desarrollo en Salud, Fonis SA20I006

Effects of recuperative holidays on Chernobyl children's 137Cs body burden

Premi UAB de la Fundació Autònoma Solidària (FAS) als millors Treballs de Fi de Grau sobre desenvolupament sostenible i justícia global. 4a Edició, curs 2019/2020The goal of this project is to study the effects recuperative holidays have on the health of children affected by radiation from the Chernobyl nuclear accident. This is accomplished by reviewing data on child 137Cs body burdens, provided by NGOs participating in recuperative holiday programmes in Belarus, and interviews of the same organizations. A statistical analysis and subsequent modelling of provided data has been conducted, showing consistent reduction in 137Cs body burden during stays away from the contaminated area, and rates of excretion and incorporation. The reduction however is not significant over time, as the original amount of 137Cs in the body is almost re-established within a year following a stay abroad. The participants improve in social and psychological aspects, and benefit from the establishment of a support network. Therefore, focus from recuperative holiday programmes should prioritize these benefits. Long-term solutions to more permanently reduce body burden should also be developed

Immune function parameters as markers of biological age and predictors of longevity

Chronological age is not a good indicator of how each individual ages and thus how to maintain good health. Due to the long lifespan in humans and the consequent difficulty of carrying out longitudinal studies, finding valid biomarkers of the biological age has been a challenge both for research and clinical studies. The aim was to identify and validate several immune cell function parameters as markers of biological age. Adult, mature, elderly and long‐lived human volunteers were used. The chemotaxis, phagocytosis, natural killer activity and lymphoproliferation in neutrophils and lymphocytes of peripheral blood were analyzed. The same functions were measured in peritoneal immune cells from mice, at the corresponding ages (adult, mature, old and long lived) in a longitudinal study. The results showed that the evolution of these functions was similar in humans and mice, with a decrease in old subjects. However, the long‐lived individuals maintained values similar to those in adults. In addition, the values of these functions in adult prematurely aging mice were similar to those in chronologically old animals, and they died before their non‐prematurely aging mice counterparts. Thus, the parameters studied are good markers of the rate of aging, allowing the determination of biological age

Altered Redox State in Whole Blood Cells from Patients with Mild Cognitive Impairment and Alzheimer’s Disease

Oxidative stress plays an essential and early role in the pathophysiology of Alzheimer’s disease (AD). Alterations in the redox state in AD and in mild cognitive impairment (MCI) patients appear in the brain and at peripheral level. Given that it is easier to study the latter, most of the research has been focused on plasma. However, the analysis of redox parameters in whole blood cells (including erythrocytes and leukocytes) has not really been investigated. Moreover, the association of these parameters with Mini-Mental State Examination (MMSE) clinical scores, has scarcely been studied. Therefore, the aim of the present work was to analyze several redox markers in whole blood cells from male and female MCI and AD patients. Antioxidant (superoxide dismutase, catalase (CAT), glutathione peroxidase (GPx), and reductase (GR) activities, and reduced glutathione (GSH) concentration) together with oxidant parameters (oxidized glutathione (GSSG) and thiobarbituric acid-reactive substances (TBARS)) were investigated using MCI and AD (10 women and 10 men in each group) and their age-matched control groups (15 women and 15 men). The results show an altered redox state in whole blood cells from AD patients (higher CAT, GSSG/GSH, TBARS and lower GPx, GR, GSH). Some of these redox parameters are already affected in MCI patients (higher TBARS and lower GPx and GR activities) in both sexes and, consequently, they could be used as markers of prodromal AD. Since GR, GSH, GSSG, and GSSG/GSH were found to be associated with MMSE scores, they seem to be useful clinically to monitor cognitive decline in AD progression