The expression of pre- and postcopulatory sexually selected traits reflects levels of dietary stress in guppies

Environmental and ecological conditions can shape the evolution of life history traits in many animals. Among such factors, food or nutrition availability can play an important evolutionary role in moderating an animal\u27s life history traits, particularly sexually selected traits. Here, we test whether diet quantity and/or composition in the form of omega-3 long chain polyunsaturated fatty acids (here termed \u27n3LC\u27) influence the expression of pre- and postcopulatory traits in the guppy (Poecilia reticulata), a livebearing poeciliid fish. We assigned males haphazardly to one of two experimental diets supplemented with n3LC, and each of these diet treatments was further divided into two diet \u27quantity\u27 treatments. Our experimental design therefore explored the main and interacting effects of two factors (n3LC content and diet quantity) on the expression of precopulatory (sexual behaviour and sexual ornamentation, including the size, number and spectral properties of colour spots) and postcopulatory (the velocity, viability, number and length of sperm) sexually selected traits. Our study revealed that diet quantity had significant effects on most of the pre- and postcopulatory traits, while n3LC manipulation had a significant effect on sperm traits and in particular on sperm viability. Our analyses also revealed interacting effects of diet quantity and n3LC levels on courtship displays, and the area of orange and iridescent colour spots in the males\u27 colour patterns. We also confirmed that our dietary manipulations of n3LC resulted in the differential uptake of n3LC in body and testes tissues in the different n3LC groups. This study reveals the effects of diet quantity and n3LC on behavioural, ornamental and ejaculate traits in P. reticulata and underscores the likely role that diet plays in maintaining the high variability in these condition-dependent sexual traits

Core stories of physicians on a Swiss internal medicine ward during the first COVID-19 wave: a qualitative exploration.

The first COVID-19 wave (2020), W1, will remain extraordinary due to its novelty and the uncertainty on how to handle the pandemic. To understand what physicians went through, we collected narratives of frontline physicians working in a Swiss university hospital during W1. Physicians in the Division of Internal Medicine of Lausanne University Hospital (CHUV) were invited to send anonymous narratives to an online platform, between 28 April and 30 June 2020. The analysed material consisted of 13 written texts and one audio record. They were examined by means of a narrative analysis based on a holistic content approach, attempting to identify narrative highlights, referred to as foci, in the texts. Five main foci were identified: danger and threats, acquisition of knowledge and practices, adaptation to a changing context, commitment to the profession, and sense of belonging to the medical staff. In physicians' narratives, danger designated a variety of rather negative feelings and emotions, whereas threats were experienced as being dangerous for others, but also for oneself. The acquisition of knowledge and practices focus referred to the different types of acquisition that took place during W1. The narratives that focused on adaptation reflected how physicians coped with W1 and private or professional upheavals. COVID-19 W1 contributed to revealing a natural commitment (or not) of physicians towards the profession and patients, accompanied by the concern of offering the best possible care to all. Lastly, sense of belonging referred to the team and its reconfiguration during W1. Our study deepens the understanding of how physicians experienced the pandemic both in their professional and personal settings. It offers insights into how they prepared and reacted to a pandemic. The foci reflect topics that are inherent to a physician's profession, whatever the context. During a pandemic, these foundational elements are particularly challenged. Strikingly, these topics are not studied in medical school, thus raising the general question of how students are prepared for the medical profession

APORTES A LA HISTORIA NATURAL DEL BAILARÍN CHICO O CACHIRLA COMÚN (ANTHUS CORRENDERA CHILENSIS)

Resumen ∙ El Bailarín Chico Común o Cachirla Común (Anthus correndera chilensis) es una de las seis subespecies del complejo A. correndera. Presenta una amplia distribución en Chile y Argentina, pero a pesar de ser un ave frecuente en su hábitat, el conocimiento de aspectos básicos de su historia natural es precario. Su distribución en Chile va desde la región de Atacama hasta Isla Navarino en la región de Magallanes, mientras que en Argentina estaría presente desde Laguna Seca, provincia de Mendoza hasta Tierra del Fuego a lo largo de los Andes, y desde Tierra del Fuego hasta el sur de la Provincia de Río Negro a lo largo de la costa Atlántica. En base a información generada en 10 localidades de Chile y Argentina, presentamos nuevos antecedentes sobre su distribución, abundancia, biometría, plumaje, canto y reproducción. A pesar de la gran cantidad de registros disponibles, hay áreas de su distribución en Argentina que requieren ser estudiadas con mayor detalle, pues se desconocen los límites con otras subespecies como correndera y catamarcae con las que podría sobreponerse. El plumaje presentó un patrón de muda similar a lo reportado para otras especies de Anthus, con una muda formativa, alterna y básica (estrategia alterna compleja). En total registramos un repertorio vocal de dos tipos de cantos: canto territorial y canto posado, y tres tipos de llamadas: de alerta, de reclamo y de solicitud de alimento de pichones. De este repertorio vocal el canto territorial es la vocalización más frecuente y compleja. Abstract ∙ Contributions to the natural history of the Correndera Pipit (Anthus correndera chilensis) Anthus correndera chilensis is one of the six subspecies of the Correndera Pipit. It is widely distributed in Chile and Argentina, but despite being common in its habitat, knowledge of essential aspects of its natural history is poor. Its distribution in Chile ranges from the region of Atacama to Isla Navarino in the Magallanes region, while in Argentina it is distributed from Laguna Seca, province of Mendoza to Tierra del Fuego along the Andes, and on a narrow strip along the Atlantic coast between Tierra del Fuego and the south of the Province of Río Negro. Based on information generated in 10 localities of Chile and Argentina, we present new information on distribution, biometry, vocalizations, breeding, and plumage/molting. Despite the large number of presence records available, there are areas of distribution in Argentina that require exploration. Because the boundaries with other subspecies, such as correndera and catamarcae, are incompletely known, range overlaps are likely. Plumage molt presented a pattern similar to that reported for other Anthus species, with a formative, alternate, and basic molting (alternate complex strategy) patterns. In total we recorded a vocal repertoire of two different song types: territorial and perched; and three call types: alert, complaint, and request of nestlings. Out of these, the most frequent and complex was the territorial song.

Physiological Studies of Chlorobiaceae Suggest that Bacillithiol Derivatives Are the Most Widespread Thiols in Bacteria

Low-molecular-weight (LMW) thiols mediate redox homeostasis and the detoxification of chemical stressors. Despite their essential functions, the distribution of LMW thiols across cellular life has not yet been defined. LMW thiols are also thought to play a central role in sulfur oxidation pathways in phototrophic bacteria, including the Chlorobiaceae. Here we show that Chlorobaculum tepidum synthesizes a novel LMW thiol with a mass of 412 ± 1 Da corresponding to a molecular formula of C14H24N2O10S, which suggests that the new LMW thiol is closely related to bacillithiol (BSH), the major LMW thiol of low-G+C Gram-positive bacteria. The Cba. tepidum LMW thiol structure was N-methyl-bacillithiol (N-Me-BSH), methylated on the cysteine nitrogen, the fourth instance of this modification in metabolism. Orthologs of bacillithiol biosynthetic genes in the Cba. tepidum genome and the CT1040 gene product, N-Me-BSH synthase, were required for N-Me-BSH synthesis. N-Me-BSH was found in all Chlorobiaceae examined as well as Polaribacter sp. strain MED152, a member of the Bacteroidetes. A comparative genomic analysis indicated that BSH/N-Me-BSH is synthesized not only by members of the Chlorobiaceae, Bacteroidetes, Deinococcus-Thermus, and Firmicutes but also by Acidobacteria, Chlamydiae, Gemmatimonadetes, and Proteobacteria. Thus, BSH and derivatives appear to be the most broadly distributed LMW thiols in biology

AtUTr1, a UDP-glucose/UDP-galactose transporter from Arabidopsis thaliana, is located in the endoplasmic reticulum and up-regulated by the unfolded protein response

Indexación: Scopus.The folding of glycoproteins in the endoplasmic reticulum (ER) depends on a quality control mechanism mediated by the calnexin/calreticulin cycle. During this process, continuous glucose trimming and UDP-glucose-dependent re-glucosylation of unfolded glycoproteins takes place. To ensure proper folding, increases in misfolded proteins lead to up-regulation of the components involved in quality control through a process known as the unfolded protein response (UPR). Reglucosylation is catalyzed by the ER lumenal located enzyme UDP-glucose glycoprotein glucosyltransferase, but as UDP-glucose is synthesized in the cytosol, a UDP-glucose transporter is required in the calnexin/calreticulin cycle. Even though such a transporter has been hypothesized, no protein playing this role in the ER yet has been identified. Here we provide evidence that AtUTr1, a UDP-galactose/glucose transporter from Arabidopsis thaliana, responds to stimuli that trigger the UPR increasing its expression around 9-fold. The accumulation of AtUTr1 transcript is accompanied by an increase in the level of the AtUTr1 protein. Moreover, subcellular localization studies indicate that AtUTr1 is localized in the ER of plant cells. We reasoned that an impairment in AtUTr1 expression should perturb the calnexin/calreticulin cycle leading to an increase in misfolded protein and triggering the UPR. Toward that end, we analyzed an AtUTr1 insertional mutant and found an up-regulation of the ER chaperones BiP and calnexin, suggesting that these plants may be constitutively activating the UPR. Thus, we propose that in A. thaliana, AtUTr1 is the UDP-glucose transporter involved in quality control in the ER.https://www.jbc.org/article/S0021-9258(19)56445-6/fulltex

Revisión sistemática de práctica de actividad física en estudiantes universitarios

La presente investigación tiene dos objetivos: (1) describir las investigaciones empíricas desarrolladas sobre la actividad física en estudiantes universitarios y (2) especificar limitaciones y orientaciones señaladas en los estudios sobre actividad física en estudiantes universitarios. El método desarrollado fue una Revisión Sistemática de las bases de datos Web of Science (WOS) y Scielo en el período de tiempo 2013 a 2018. Los resultados del primer objetivo son descripción de los estudios respecto del país, diseño, muestra, objetivos, e instrumentos de medida de las investigaciones. Respecto de los resultados del segundo objetivo, las dos principales limitaciones declaradas en los estudios son el uso de instrumentos de medida de tipo autorreporte y los diseños que son principalemente correlaciónales y escasos cuasiexperimento; las dos principales orientaciones son que las universidades fomenten la actividad física a través de programas de intervención y que sea integrada al currículum

Damage evaluation during installation of geosynthetics used in asphalt pavements

Geosynthetics are commonly used as anti-reflective cracking systems in asphalt pavements. The rehabilitation design methods use the characteristics of as-received geosynthetics as inputs. However, these materials undergo physical damage during their installation due to mechanical and thermal loads which currently are not taken into account in the design processes. These loads can produce a reduction in geosynthetic strength and therefore, it is necessary to know the secant modulus after installation in order to improve the pavement design incorporating these materials. The secant modulus of a material indicates its initial stiffness. This paper describes an experimental study of damage due to installation of five different geosynthetics using three different procedures: (i) mechanical damage induced in the laboratory considering the action of aggregates, (ii) in situ mechanical and thermal damage due to actual installation in a test section, and (iii) a new mechanical and thermal damage experimental test developed with the aim of reproducing the real installation conditions. The main results of the study indicate that the obtained secant modulus of the tested geosynthetics reduced after applying the three damage procedures, and the loss of properties differed depending on the type and constitutive material and on the applied damage procedure.This investigation was supported by the research Project ‘Rehabilitation of roads and highways (REHABCAR)’ file number IPT-370000–2010–029, led by DRAGADOS (ACS Group), in collaboration with GEOCISA and ASFALTOS AUGUSTA among others. The project has been funded by the Ministry of Economy and Competitiveness (MINECO) within the National Plan for Scientific Research, Development and Innovation 2008–2011 (INNPACTO 2010) and the European Union under ERDF Funds (European Regional Development Fund)

Mitochondrial phylogeography and demographic history of the Vicuña: implications for conservation

The vicuña (Vicugna vicugna; Miller, 1924) is a conservation success story, having recovered from near extinction in the 1960s to current population levels estimated at 275 000. However, lack of information about its demographic history and genetic diversity has limited both our understanding of its recovery and the development of science-based conservation measures. To examine the evolution and recent demographic history of the vicuña across its current range and to assess its genetic variation and population structure, we sequenced mitochondrial DNA from the control region (CR) for 261 individuals from 29 populations across Peru, Chile and Argentina. Our results suggest that populations currently designated as Vicugna vicugna vicugna and Vicugna vicugna mensalis comprise separate mitochondrial lineages. The current population distribution appears to be the result of a recent demographic expansion associated with the last major glacial event of the Pleistocene in the northern (18 to 22°S) dry Andes 14–12 000 years ago and the establishment of an extremely arid belt known as the 'Dry Diagonal' to 29°S. Within the Dry Diagonal, small populations of V. v. vicugna appear to have survived showing the genetic signature of demographic isolation, whereas to the north V. v. mensalis populations underwent a rapid demographic expansion before recent anthropogenic impacts

Fish oil replacement in current aquaculture feed : is cholesterol a hidden treasure for fish nutrition?

Teleost fish, as with all vertebrates, are capable of synthesizing cholesterol and as such have no dietary requirement for it. Thus, limited research has addressed the potential effects of dietary cholesterol in fish, even if fish meal and fish oil are increasingly replaced by vegetable alternatives in modern aquafeeds, resulting in progressively reduced dietary cholesterol content. The objective of this study was to determine if dietary cholesterol fortification in a vegetable oil-based diet can manifest any effects on growth and feed utilization performance in the salmonid fish, the rainbow trout. In addition, given a series of studies in mammals have shown that dietary cholesterol can directly affect the fatty acid metabolism, the apparent in vivo fatty acid metabolism of fish fed the experimental diets was assessed. Triplicate groups of juvenile fish were fed one of two identical vegetable oil-based diets, with additional cholesterol fortification (high cholesterol, H-Chol) or without (low cholesterol, L-Chol), for 12 weeks. No effects were observed on growth and feed efficiency, however, in fish fed H-Col no biosynthesis of cholesterol, and a remarkably decreased apparent in vivo fatty acid b-oxidation were recorded, whilst in LChol fed fish, cholesterol was abundantly biosynthesised and an increased apparent in vivo fatty acid b-oxidation was observed. Only minor effects were observed on the activity of stearyl-CoA desaturase, but a significant increase was observed for both the transcription rate in liver and the apparent in vivo activity of the fatty acid D-6 desaturase and elongase, with increasing dietary cholesterol. This study showed that the possible effects of reduced dietary cholesterol in current aquafeeds can be significant and warrant future investigations