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Anaerobic digestion is a well-established technology for the sustainable production of biogas. However, to be used as a substitute for natural gas or as vehicle fuel, it is necessary to remove carbon dioxide (CO2) and other contaminants from biogas that can compromise the useful life of combustion engines. Upgraded biogas is known as biomethane (>95% methane content). This work reviews the different technologies used for upgrading biogas, emphasizing microalgae–nanoparticle systems, representing a more sustainable and environmentally friendly system. Parameters affecting these systems performance are discussed, and the trends and areas of opportunity for subsequent work are evaluated through a bibliometric analysis.

Abstract Background and aims Despite that 93% of people indicate that a mattress plays a pivotal role in achieving high‐quality sleep, there is a scarcity of research investigating the influence of mattresses on sleep quality, pain, and mood in nonclinical poor sleepers. The purpose was to examine the effectiveness of a pressure‐releasing medium‐firm grid mattress on sleep and health outcomes (e.g., mood, pain, daytime fatigue) of adults with nonclinical insomnia symptoms using a quasi‐experimental design. Methods Participants were 39 adults (mean age = 45.29) with nonclinical insomnia (i.e., occasional sleeplessness). Following 1 week of baseline assessments on their current mattress, they slept on a pressure‐relieving grid mattress for 8 weeks. Participants completed self‐report assessments of the Pittsburgh Sleep Quality Index, Berlin Questionnaire, Insomnia Severity Index, Restorative Sleep Questionnaire, Perceived Stress Scale, Profile of Mood States, Daytime Fatigue Scale, Pain and Sleep Questionnaire, and Brief Pain Inventory at Baseline and Weeks 1, 2, 3, 4, and 8. Participants continually wore an Oura Ring to objectively assess sleep and daytime activity. The data were collected from January 2022 to April 2022 and were stored electronically. Repeated‐measures analyses of variance were used to analyze mean time differences. Results Self‐reported sleep quality, perceived pain, perceived stress, mood, and daytime fatigue improved significantly from Baseline to Week 8, p's

Mechanical site preparation (MSP) is used prior to planting to control competing vegetation and enhance soil conditions, particularly in areas prone to paludification. Tree planting density can be adapted to the management context and objectives, as it influences yield and wood quality. However, the combined effects of MSP and planting density on understory vegetation composition, functional traits, and diversity remain uncertain. We thus conducted a study in the Clay Belt region of northwestern Quebec, Canada. After careful logging, the study area was divided into nine sites, each receiving one of three treatments: plowing, disc trenching, or no preparation. Sites were further divided into two, with black spruce (Picea mariana [Mill.] Britton, Sterns & Poggenb.) seedlings planted at either a low planting density of 1100 seedlings ha-1 or a high planting density of 2500 seedlings ha-1. After nine years, we assessed understory composition, diversity, key functional traits, sapling density and growth of planted trees. Careful logging alone led to a higher density of naturally established conifers compared to plowing or disc trenching. The interaction between planting density and MSP significantly influenced understory diversity and composition in plowed plots. Understory composition was affected by the soil C/N ratio, coniferous species, and deciduous species density. The growth of black spruce was notably enhanced with higher planting density in the plow treatment only. Neither planting density nor MSP alone affected tree height and diameter. Our results suggest that combining plowing with high-density planting can enhance stand growth and improve forest productivity. These findings guide future research on paludified forests.

Most wastewater treatment plants use activated sludge-based biological systems for this purpose. The latter must effectively remove organic matter and, at the same time, show good sedimentability. However, sometimes there is an excessive proliferation of certain bacteria, giving rise to filamentary swelling, compromising the excellent sedimentability of the sludge. In this sense, the study’s objective was to evaluate the effect of applying two different technologies, the application of low-frequency ultrasound and UV radiation. Some bench-scale experiments were performed using the bulked sludge from the secondary clarifier of a wastewater treatment facility in an industrial park (CIVAC) in Morelos, Mexico, affected by filamentous organisms. Results showed that for the UV application for two, four, and 6 min, the settleability of the mixed liquor suspended solids was not improved; on the other hand, the cavitation effect caused by the ultrasound application demonstrated effective action against the destruction of filamentous organisms. The 10 min condition showed a significant decrease in the filament integrity of the microorganisms and a significant improvement of sedimentation velocity and sludge volume index (SVI) values and settleability of the sludge, but not enough to satisfy national discharge regulations related to total suspended solids in the treated effluent. Molecular identification indicates the presence of the genera Thauera and Brevundimonas in the sludge.

Introduction and objectives: After hepatitis A (HAV) mandatory immunization in 2005 in Argentina, the incidence of HAV declined drastically. However, several new autochthonous cases of HAV have been reported since 2017. We aimed to evaluate the clinical and epidemiological characteristics and possible transmission routes of affected patients. Patients or Materials and methods: We performed a cross-sectional study of patients residing in Argentina with acute hepatitis A between 30.06.2017 and 31.12.2018. Results: 66 cases of HAV were registered. Fifty-six patients (86%) were males, with a mean age of 34 ± 12 years old. The most likely routes of transmission were sexual intercourse of men with men, reported by 31 patients. Additionally, 23% and 26% of patients tested positive for HIV and syphilis, respectively. In total, 35% of patients required hospitalization. When assessing outcomes, 79% had a mild presentation and 21% had a severe/fulminant presentation: one patient underwent liver transplantation, and one patient died. Conclusions: Our study describes that during the study period, HAV infection affected predominantly young adults, particularly men who have sex with men. An elevated proportion of them was diagnosed with a concomitant sexually transmitted disease, and several patients had a severe presentation of the disease.

The purpose of this study was to understand the experiences of college athletes who were directly impacted by their institution’s pursuit of gaining membership to a different NCAA division (i.e., divisional reclassification). More specifically, this study sought to understand specific changes that accompany the Division III to Division II transition, which include: 1) divisional philosophy, 2) financial aid, 3) level of competition, 4) athletically related activities, and 5) academic standards. Conceptually, this study was guided by the stress appraisal and coping process. The Brief COPE inventory of coping responses was applied as a framework from which to understand how college athletes coped with the financial, athletic, and academic changes to the college athlete experience. Research participants were Division III college athletes who reclassified with their athletic program to become Division II college athletes, and who participated in semi-structured interviews that allowed for rich descriptions of their experiences through the reclassification process to be captured. Findings suggest that reclassification was a relative stressor meaning that the process was perceived as stressful by some but not all the reclassifying college athletes interviewed. In coping with the relative stresses, college athletes demonstrated a greater tendency to engage in emotion-focused coping, which included the venting of emotional distress. More specialist support services are proposed to encourage more problem-focused coping responses among affected college athletes.

Copious research demonstrates the benefits of adding active learning to traditional lectures to enhance learning and reduce failure/withdrawal rates. However, many questions remain about how best to implement active learning to maximize student outcomes. This paper investigates several “second generation” questions regarding infusing active learning, via Think-Pair-Share (TPS), into a large lecture course in Computer Science. During the “Share” phase of TPS, what is the best way to debrief the associated course concepts with the entire class? Specifically, does student learning differ when instructors debrief the rationale for every answer choice (full debrief) versus only the correct answer (partial debrief)? And does the added value for student outcomes vary between tasks requiring recall versus deeper comprehension and/or application of concepts? Regardless of discipline, these questions are relevant to instructors implementing TPS with multiple-choice questions, especially in large lectures. Similar to prior research, when lectures included TPS, students performed significantly better (~13%) on corresponding exam items. However, students’ exam performance depended on both the type of debrief and exam questions. Students performed significantly better (~5%) in the full debrief condition than the partial debrief condition. Additionally, benefits of the full debrief condition were significantly stronger (~5%) for exam questions requiring deeper comprehension and/or application of underlying Computer Science processes, compared to simple recall. We discuss these results and lessons learned, providing recommendations for how best to implement TPS in large lecture courses in STEM and other disciplines.

Introduction and aim: Liver transplantation (LT) for acute liver failure (ALF) still has a high early mortality. We aimed to evaluate changes occurring in recent years and identify risk factors for poor outcomes. Material and methods: Data were retrospectively obtained from the Argentinean Transplant Registry from two time periods (1998–2005 and 2006–2016). We used survival analysis to evaluate risk of death. Results: A total of 561 patients were listed for LT (69% female, mean age 39.5 ± 16.4 years). Between early and later periods there was a reduction in wait-list mortality from 27% to 19% (p

When a farm that was using a conventional milking system introduces an automatic milking system (AMS) possible risk factors can affect milk quality. The aim of the study was to investigate the influence of milking with automatic milking systems on milk quality variables over a long time-period post-installation. Bulk milk total bacterial count (BMTBC) and somatic cell count (BMSCC) were analysed and compared from 2 years before introduction of automatic milking until 4 years after. Differences regarding these quality parameters were contrasted using t-test and one-way analysis of variance (ANOVA) and post hoc comparisons were performed. A significant increase in BMTBC was observed during the first three months after introduction of AMS, counts then declined to equivalent levels pre-AMS installation, from 25,000 to 50,000 cfu mL−1. Although differences were significant for the first two years post-installation, they became non-significant during the following two years. The difference in BMSCC was not statistically significant between pre and post-AMS installation time periods, but by grouping data into annual periods, significantly higher values of BMSCC were found during the first year after introduction. Nevertheless, these values decreased over time and even showed a significant improvement in the third year with respect to pre-introduction. The data show that the installation of AMS had a marked impact on milk quality. However, as soon as farmers become accustomed to managing the new equipment and the adaption of cows is real, a level of milk quality which can be maintained over time is achievable.

This study presents a systematic review of 169 papers concerning the ICT (Information and Communication Technologies) related to rural areas, specifically to dairy farms. The objective was to delve into the relationship between dairy farmers and the administrative authorities via e-government, comparing this area to another eight concerning the farmer’s needs and expectations in relation to the ICT in different fields of their business. We observed that areas such as connectivity and digital inclusion are the most covered areas not only at the study level but also at the government level since countries all over the world are trying to develop politics to put an end to the so-called “digital divide,” which affects rural areas more intensely. This is increasing due to the growing technological innovations. The areas of the market, production, financial development, management and counseling, Smart Farming, and Internet of Things have been approached, associated with the ICT in dairy farms, showing in the latter two an increasing number of papers in the last few years. The area of public administration in relation to dairy farms has also been covered, being remarkable the low number of pieces of research concerning the interaction by the farmers, more specifically by dairy farmers, with the public administration, which is surprising due to the new global need and especially in the European Union (EU) of interacting with it telematically by all legal entities. The results show that there are still barriers to the implementation of the electronic government (e-government) since the websites do not meet the user’s expectations. Therefore, this study lays the ground for future research on this area. As a graphical abstract of the contributions of this paper, we present a graphic summary, where the different contributions by areas and expressed in percentage values are shown.

Postweaning is one of the most sensitive and energy-demanding phases of swine production. The objective of this research was to assess the energy, production and environmental characteristics of a conventional farm with temperature-based environmental control. The selected energy, environmental and production variables were measured on farm, in a high livestock density area of NW Spain, for seven production cycles. The quantification of variables was aimed at obtaining the maximum performance with the lowest possible use of resources, focusing on animal welfare and production efficiency. The Brown–Forsythe, Welch and Games-Howell tests revealed significant differences in terms of temperature, relative humidity and CO2 concentrations among production cycles, and among the critical, postcritical and final periods. Improved humidity management resulted in a 17% reduction of climate control energy, which involved energy savings in the range of 33% to 47% per kg produced at the end of the postweaning cycle. Accordingly, adding humidity as a control variable could result in higher ventilation rates, thereby improving animal welfare, reducing heating energy use and increasing weight gain per unit climate control energy. In addition, the strong correlations found between heating energy and relative humidity (R2 = 0.73) and ventilation energy and CO2 (R2 = 0.99) suggest that these variables could be readily estimated without additional sensor costs.

Antecedentes: El bevacizumab pertenece a una familia de medicamentos que inhiben la acción de los factores endoteliales de crecimiento vascular (VEGF, por sus siglas en inglés) aprobado por la FDA para el tratamiento de varios tipos de cáncer. Es un anticuerpo monoclonal que se une a todas las isoformas del VEGF evitando que la molécula se una a su receptor y active sus vías efectoras, disminuyendo así la proliferación de nuevos vasos inestables que por medio de fugas y rupturas que causan la acumulación de líquido en el espacio subrretiniano. Se ha utilizado de manera off-label para el tratamiento de las patologías proliferativas de la retina o coroides, con resultados prometedores. Objetivo: Determinar el efecto de la administración de 3 dosis de bevacizumab intravítreo sobre el grosor macular central medido por tomografía de coherencia óptica (OCT) después de 1 mes. Establecer una base de datos de las características epidemiológicas de los pacientes – edad, género, indicación de tratamiento, historia de diabetes e historia familiar de ceguera – y la respuesta al tratamiento con bevacizumab intravítreo. Metodología: Es un estudio cuasi-experimental retrospectivo de antes y después de una intervención. Se revisaron 261 expedientes clínicos para obtener los datos generales del paciente así como la medida de grosor macular central antes y 1 mes después de la administración de bevacizumab intravítreo por cualquier indicación. Los resultados luego fueron comparados utilizando la prueba T de Student para la diferencia de dos medias. Resultados: Al analizar a toda la población del estudio, se obtuvo una reducción de grosor macular central antes y después de la administración de bevacizumab de 19% (p < 0.0001). Esta diferencia no se observó en todos los grupos de pacientes al compararlos según la indicación de tratamiento. Conclusión: Se pudo observar un cambio significativo en la reducción del grosor macular central tras la administración de 3 dosis de bevacizumab intravítreo.

En esta segunda entrega continuamos con los Memoriales dejados por los provinciales a las estancias de Alta Gracia y Caroya, el Convictorio de Nuestra Señora de Monserrat, las estancias de Jesús María y Candelaria, el Noviciado y las estancias de San Ignacio de Calamuchita y Santa Catalina.

Los Memoriales son una tipología de documentos emanados por el provincial y dirigidos hacia quien estaba al frente de un domicilio. Estos últimos pueden ser institucionales como los enviados a los Colegios, el Noviciado y el Convictorio, o bien a las estancias e incluso a las reducciones. Eran instrucciones precisas que tendían a la buena administración espiritual y material, y hasta de pequeños detalles que corregían situaciones de una amplia variedad que generalmente no concordaban con las normas del Instituto. No eran precisamente apologéticos, sino muy críticos en cuanto debían mejorar aspectos de regular o mal funcionamiento. Se redactaban luego de las periódicas visitas que realizaban los provinciales y de cuyas observaciones vertían las indicaciones.

We present some reflections about using cartoons as an innovative tool for teaching science, as well as for contribute in the practice by teacher researchers. This ideas were part of the results obtained in the seminar "Cartoons", offered by the research group “Physics Education”, into the "First Festival, Art and Science for convivence" by Maloka in May, 2009. We analyzed the particular case for physics teaching based on cartoons, thinking about what that's means in physics didactic.

Many modern sports stadia around the world consume large amounts of energy during their dayto- day operations. With the cost of this energy constantly on the rise, the challenge of managing this uncontrolled cost has become increasingly more important for the successful and sustainable operation of these facilities. It is essential that some form of energy management system be embraced by these sports stadia. This paper is a case study on Aviva Stadium’s recent implementation of the ISO 50001 Energy Management System. The authors identify the potential challenges and benefits of implementing the ISO 50001 Energy Management System in sports stadia. Final certification to the standard came on the 25th of September 2013 making Aviva Stadium the first stadium in the world to have achieved thirdparty certification to the ISO 50001 standard. This paper can act as a guide for other stadia wishing to adapt ISO 50001 to their venue, especially since it resulted in a €1 million energy cost avoidance over a three-year period.

Losses of plant species diversity can affect ecosystem functioning, with decreased primary productivity being the most frequently reported effect in experimental plant assemblages, including tree plantations. Less is known about the role of biodiversity in natural ecosystems, including forests, despite their importance for global biogeochemical cycling and climate. In general, experimental manipulations of tree diversity will take decades to yield final results. To date, biodiversity effects in natural forests therefore have only been reported from sample surveys or meta-analyses with plots not initially selected for diversity. We studied biomass and growth of subtropical forests stands in southeastern China. Taking advantage of variation in species recruitment during secondary succession, we adopted a comparative study design selecting forest plots to span a gradient in species richness. We repeatedly censored the stem diameter of two tree size cohorts, comprising 93 species belonging to 57 genera and 33 families. Tree size and growth were analyzed in dependence of species richness, the functional diversity of growth-related traits, and phylogenetic diversity, using both general linear and structural equation modeling. Successional age covaried with diversity, but differently so in the two size cohorts. Plot-level stem basal area and growth were positively related with species richness, while growth was negatively related to successional age. The productivity increase in species-rich, functionally and phylogenetically diverse plots was driven by both larger mean sizes and larger numbers of trees. The biodiversity effects we report exceed those from experimental studies, sample surveys and meta-analyses, suggesting that subtropical tree diversity is an important driver of forest productivity and re-growth after disturbance that supports the provision of ecological services by these ecosystems.

The Earth's rotation has driven the evolution of cellular circadian clocks to facilitate anticipation of the solar cycle. Some evidence for timekeeping mechanism conserved from early unicellular life through to modern organisms was recently identified, but the components of this oscillator are currently unknown. Although very few clock components appear to be shared across higher species, Casein Kinase 1 (CK1) is known to affect timekeeping across metazoans and fungi, but has not previously been implicated in the circadian clock in the plant kingdom. We now show that modulation of CK1 function lengthens circadian rhythms in Ostreococcustauri, a unicellular marine algal species at the base of the green lineage, separated from humans by ~1.5 billion years of evolution. CK1 contributes to timekeeping in a phase-dependent manner, indicating clock-mediated gating of CK1 activity. Label-free proteomic analyses upon overexpression as well as inhibition revealed CK1-responsive phosphorylation events on a set of target proteins, including highly conserved potentially clock-relevant cellular regulator proteins. These results have major implications for our understanding of cellular timekeeping and can inform future studies in any circadian organism.

En este escrito se presentan algunas de las reflexiones acerca del uso de los dibujos animados como una herramienta innovadora para la enseñanza ciencias, y sobre el ejercicio del docente como investigador, que hacen parte de los resultados que se obtuvieron en el seminario “Dibujos animados” que el grupo de investigación “Enseñanza y Aprendizaje de la Física” desarrolló en el primer Festival de Arte y Ciencia para la Convivencia, realizado por Maloka en Bogotá, 2009. Analizamos el caso particular de la enseñanza de la física a partir de los dibujos animados y su significado en la didáctica de la física.