Irrigation is a land management practice with major environmental impacts. However, global energy consumption and carbon emissions resulting from irrigation remain unknown. We assess the worldwide energy consumption and carbon emissions associated with irrigation,while also measuring the potential energy and carbon reductions achievable through the adoption of efficient and low-carbon irrigation practices. Currently, irrigation contributes 216 million metric tons of CO2 emissions and consumes 1896 petajoules of energy annually, representing 15% of greenhouse gas emissions and energy utilized in agricultural operations. Despite only 40% of irrigated agriculture relies on groundwatersources, groundwater pumping accounts for 89% of the total energy consumption in irrigation. Projections indicate that future expansion of irrigation could lead to a 28% increase in energy usage. Embracing highly efficient, low-carbon irrigation methods has the potential to cut energy consumption in half and reduce CO2 emissions by 90%. However, considering country-specific feasibility of mitigation options, global CO2 emissions may only see a 55% reduction. Our research offers comprehensive insights into the energy consumption and carbon emissions associated with irrigation, contributing valuable information that can guide assessments of the viability of irrigation in enhancing adaptive capacity within the agricultural sector.

The potential of enhanced agricultural management practices to drive sustainability is rarely quantified at grassroots level. Here we analyse nitrogen use and loss in Chinese cropland, drawing from data collected in 2,238,550 sites in two national agricultural pollution source censuses from 2007 to 2017. We find an upswing of 10% in crop yields and an 8% reduction in nitrogen pollution during this period, owing to the promotion and adoption of various management practices (including the combination of organic and chemical fertilizers, straw recycling and deep placement of fertilizer). These practices have collectively contributed to an 18% increase in nitrogen use efficiency in the country. By fully embracing them, we project that annual cropland pollution could be further reduced by up to 1.4 Mt of nitrogen without compromising crop yields. Environmental and human health benefits are projected to consistently outweigh implementation costs in the future, with total benefits reaching US$15 billion.

Background: Temperate subalpine lakes recovering from eutrophication in central Europe are experiencing harmful blooms due to the proliferation of Planktothrix rubescens, a potentially toxic cyanobacteria. To optimize the management of cyanobacteria blooms there is the need to better comprehend the combination of factors influencing the diversity and dominance of cyanobacteria and their impact on the lake's ecology. The goal of this study was to characterize the diversity and seasonal dynamics of cyanobacteria communities found in a water column of Lake Geneva, as well as the associated changes on bacterioplankton abundance and composition.Methods: We used 16S rRNA amplicon high throughput sequencing on more than 200 water samples collected from surface to 100 meters deep monthly over 18 months. Bacterioplankton abundance was determined by quantitative PCR and PICRUSt predictions were used to explore the functional pathways present in the community and to calculate functional diversity indices.Results: The obtained results confirmed that the most dominant cyanobacteria in Lake Geneva during autumn and winter was Planktothrix (corresponding to P. rubescens). Our data also showed an unexpectedly high relative abundance of picocyanobacterial genus Cyanobium, particularly during summertime. Multidimensional scaling of Bray Curtis dissimilarity revealed that the dominance of P. rubescens was coincident with a shift in the bacterioplankton community composition and a significant decline in bacterioplankton abundance, as well as a temporary reduction in the taxonomic and PICRUSt2 predicted functional diversity.Conclusion: Overall, this study expands our fundamental understanding of the seasonal dynamics of cyanobacteria communities along a vertical column in Lake Geneva and the ecology of P. rubescens, ultimately contributing to improve our preparedness against the potential occurrence of toxic blooms in the largest lake of western Europe.

While natural communities can contain hundreds of species, modern coexistence theory focuses primarily on species pairs. Alternatively, the structural stability approach considers the feasibility of equilibria, gaining scalability to larger communities but sacrificing information about dynamic stability. Three-species competitive communities are a bridge to more-diverse communities. They display novel phenomena while remaining amenable to mathematical analysis, but remain incompletely understood. Here, we combine these approaches to identify the key quantities that determine three-species competition outcomes. We show that pairwise niche overlap and fitness differences are insufficient to completely characterize competitive outcomes, which requires a strictly triplet-wise quantity: cyclic asymmetry, which underlies intransitivity. Low pairwise niche overlap stabilizes the triplet, while high fitness differences promote competitive exclusion. The effect of cyclic asymmetry on stability is complex and depends on pairwise niche overlap. In summary, we elucidate how pairwise niche overlap, fitness differences and cyclic asymmetry determine three-species competition outcomes.

We present optical observations of the Swift short-duration gamma-ray burst (GRB) GRB 161104A and its host galaxy at z = 0.793 +/- 0.003. We model the multiband photometry and spectroscopy with the stellar population inference code Prospector and explore the posterior using nested sampling. We find a mass-weighted age of t(m) = 2.12(-0.21)(+0.23) Gyr, stellar mass of log(M/M-circle dot) = 10.21 +/- 0.04, metallicity of log(Z/Z(circle dot)) = 0.08(-0.06)(+0.05), dust extinction of A(V) = 0.08(-0.05)(+0.08), and low star formation rate of 9.9 x 10(-2) Me yr(-1). These properties, along with a prominent 4000 angstrom break and optical absorption lines, classify this host as an early-type, quiescent galaxy. Using Dark Energy Survey galaxy catalogs, we demonstrate that the host of GRB 161104A resides on the outskirts of a galaxy cluster at z approximate to 0.8, situated approximate to 1 Mpc from the likely brightest cluster galaxy. We also present new modeling for 20 additional short GRB hosts (approximate to 33% of which are early-type galaxies), finding population medians of log(M/M-circle dot) = 9.94(-0.98)(+0.88) and t(m) = 1.07(-0.67)(+1.98) Gyr (68% confidence). We further find that the host of GRB 161104A is more distant, less massive, and younger than the four other short GRB hosts known to be associated with galaxy clusters. Cluster short GRBs have faint afterglows, in the lower approximate to 11% (approximate to 30%) of observed X-ray (optical) luminosities. We place a lower limit on the fraction of short GRBs in galaxy clusters versus those in the field of approximate to 5%-13%, consistent with the fraction of stellar mass of approximate to 10%-20% in galaxy clusters at redshifts 0.1 <= z <= 0.8. Future studies that take advantage of wider-field and deeper cluster surveys are needed to understand the true rate of short GRBs in clusters and their effect on heavy-element enrichment in the intracluster medium.

The bioluminescent bacterium Vibrio fischeri forms a mutually beneficial symbiosis with the Hawaiian bobtail squid, Euprymna scolopes, in which the bacteria, housed inside a specialized light organ, produce light used by the squid in its nocturnal activities. Upon hatching, E. scolopes juveniles acquire V. fischeri from the seawater through a complex process that requires, among other factors, chemotaxis by the bacteria along a gradient of N-acetylated sugars into the crypts of the light organ, the niche in which the bacteria reside. Once inside the light organ, V. fischeri transitions into a symbiotic, sessile state in which the quorum-signaling regulator LitR induces luminescence. In this work we show that expression of litR and luminescence are repressed by a homolog of the V. cholerae virulence factor TcpP, which we have named HbtR. Further, we demonstrate that LitR represses genes involved in motility and chemotaxis into the light organ and activates genes required for exopolysaccharide production. ImportanceTcpP homologs are widespread throughout the Vibrio genus; however, the only protein in this family described thus far is a V. cholerae virulence regulator. Here we show that HbtR, the TcpP homolog in V. fischeri, has both a biological role and regulatory pathway completely unlike that in V. cholerae. Through its repression of the quorum-signaling regulator LitR, HbtR affects the expression of genes important for colonization of the E. scolopes light organ. While LitR becomes activated within the crypts, and upregulates luminescence and exopolysaccharide genes and downregulates chemotaxis and motility genes, it appears that HbtR, upon expulsion of V. fischeri cells into seawater, reverses this process to aid the switch from a symbiotic to a planktonic state. The possible importance of HbtR to the survival of V. fischeri outside of its animal host may have broader implications for the ways in which bacteria transition between often vastly different environmental niches.

IntroductionGestational diabetes mellitus (GDM) is associated with adverse perinatal outcomes. Approaches to screening for GDM continue to evolve, introducing potential variability of care. This study explored the impact of these variations on GDM counselling and screening from the perspectives of pregnant individuals. MethodsFollowing a Corbin and Strauss approach to qualitative, grounded theory we recruited 28 individuals from three cities in Ontario, Canada who had a singleton pregnancy under the care of either a midwife, family physician or obstetrician. Convenience and purposive sampling techniques were used. Semi-structured telephone interviews were conducted and transcribed verbatim between March and December 2020. Transcripts were analysed inductively resulting in codes, categories and themes. ResultsThree themes were derived from the data about GDM screening and counselling: 'informing oneself', 'deciding' and 'screening'. All participants, regardless of geographical region, or antenatal care provider, moved through these three steps during the GDM counselling and screening process. Differences in counselling approaches between pregnancy care providers were noted throughout the 'informing' and 'deciding' stages of care. Factors influencing these differences included communication, healthcare autonomy and patient motivation to engage with health services. No differences were noted within care provider groups across the three geographic regions. Participant experiences of GDM screening were influenced by logistical challenges and personal preferences towards testing. ConclusionInforming oneself about GDM may be a crucial step for facilitating decision-making and screening uptake, with an emphasis on information provision to facilitate patient autonomy and motivation. Patient or Public ContributionParticipants of our study included patients and service users. Participants were actively involved in the study design due to the qualitative, patient-centred nature of the research methods employed. Analysis of results was structured according to the emergent themes of the data which were grounded in patient perspectives and experiences.

Gestational diabetes mellitus (GDM) is associated with adverse health outcomes for the pregnant individual and their baby. Screening approaches for GDM have undergone several iterations, introducing variability in practice among healthcare providers. As such, our study aimed to explore the views of antenatal providers regarding their practices of, and counseling experiences on the topic of, GDM screening in Ontario. We conducted a qualitative, grounded theory study. The study population included antenatal providers (midwives, family physicians, and obstetricians) practicing in Hamilton, Ottawa, or Sudbury, Ontario. Semi-structured telephone interviews were conducted and transcribed verbatim. Transcripts were analyzed using inductive coding upon which codes, categories, and themes were developed to generate a theory grounded in the data. Twenty-two participants were interviewed. Using the social-ecological theory, we created a model outlining four contextual levels that shaped the experiences of GDM counseling and screening: Intrapersonal factors included beliefs, knowledge, and skills; interpersonal factors characterized the patient-provider interactions; organizational strengths and challenges shaped collaboration and health services infrastructure; and finally, guidelines and policies were identified as systemic barriers to health care access and delivery. A focus on patient-centered care was a guiding principle for all care providers and permeated all four levels of the model. Patient-centered care and close attention to barriers and facilitators across intrapersonal, interpersonal, organizational, and policy domains can minimize the impact of variations in GDM screening guidelines. Among care providers, there is a desire for additional skill development related to GDM counseling, and for national consensus on optimal screening guidelines.

Perovskite nanocrystals have attracted much attention in the last ten years due to their different applications, especially in the photovoltaic domain and LED performance. In this large family of perovskite nanocrystals, CsPbBr3 nanocrystals are attractive nanomaterials because they are good candidates for obtaining green emissions and exploring new synthesis routes. In this context, controlling the nanometric scale's morphology, particularly the size and monodispersity, is fundamental for exploring their photophysical properties and final applications. Currently, the nanometric size of nanocrystals is ensured by the presence of oleic acid and oleylamine molecules, in using Hot Injection (HI) or ligand-assisted reprecipitation (LARP) methods. If oleic acid plays a fundamental role, oleylamine can be easily substituted by other amino molecules, opening the way for the functionalization of CsPbBr3 nanocrystals and the obtention of new hybrid perovskite nanocrystal families. In this article, we describe the synthesis, by soft chemistry, of a new family of hybrid organic-inorganic CsPbBr3 nanocrystals, functionalized by aryl-alkylamine (AAA) molecules, through the modified LARP method. We highlight the mechanism for cutting submicron crystals into nanocrystals, using aryl-alkylamine molecules like scissors. The impact of these amino molecules on the final nanocrystals leads to different nanocrystal morphologies (nanocubes, nanosheets, or nanorods) and structures (monoclinic, rhombohedral, or tetragonal). In addition, this modified LARP method highlights, under certain experimental conditions, an unexpected formation of PbO ribbons.

Lakes and reservoirs globally are experiencing unprecedented changes in land use and climate, depleting dissolved oxygen (DO) in the bottom waters (hypolimnia) of these ecosystems. Because DO is the most energetically favorable terminal electron acceptor (TEA) for organic carbon mineralization, its availability controls the onset of alternate TEA pathways (for example, denitrification, manganese reduction, iron reduction, sulfate reduction, methanogenesis). Low DO concentrations can trigger organic carbon mineralization via alternate TEA pathways in the water column and sediments, which has important implications for greenhouse gas production [carbon dioxide (CO2) and methane (CH4)]. In this study, we experimentally injected supersaturated DO into the hypolimnion of a eutrophic reservoir and measured concentrations of TEAs and terminal electron products (TEPs) in the experimental reservoir and an upstream reference reservoir. We calculated the electron equivalents yielded from each TEA pathway and estimated the contributions of each TEA pathway to organic carbon processing in both reservoirs. DO additions to the hypolimnion of the experimental reservoir promoted aerobic respiration, suppressing most alternate TEA pathways and resulting in elevated CO2 accumulation. In comparison, organic carbon mineralization in the reference reservoir's anoxic hypolimnion was dominated by alternate TEA pathways, resulting in both CH4 and CO2 accumulation. Our ecosystemscale experiments demonstrate that the alternate TEA pathways that succeed aerobic respiration in lakes and reservoirs can be manipulated at the ecosystem scale. Moreover, changes in the DO dynamics of freshwater lakes and reservoirs may result in concomitant changes in the redox reactions in the water column that control organic carbon mineralization and greenhouse gas accumulation.