Unforeseen plant phenotypic diversity in a dry and grazed world.

Earth harbours an extraordinary plant phenotypic diversity1 that is at risk from ongoing global changes2,3. However, it remains unknown how increasing aridity and livestock grazing pressure-two major drivers of global change4-6-shape the trait covariation that underlies plant phenotypic diversity1,7. Here we assessed how covariation among 20 chemical and morphological traits responds to aridity and grazing pressure within global drylands. Our analysis involved 133,769 trait measurements spanning 1,347 observations of 301 perennial plant species surveyed across 326 plots from 6 continents. Crossing an aridity threshold of approximately 0.7 (close to the transition between semi-arid and arid zones) led to an unexpected 88% increase in trait diversity. This threshold appeared in the presence of grazers, and moved toward lower aridity levels with increasing grazing pressure. Moreover, 57% of observed trait diversity occurred only in the most arid and grazed drylands, highlighting the phenotypic uniqueness of these extreme environments. Our work indicates that drylands act as a global reservoir of plant phenotypic diversity and challenge the pervasive view that harsh environmental conditions reduce plant trait diversity8-10. They also highlight that many alternative strategies may enable plants to cope with increases in environmental stress induced by climate change and land-use intensification.

Aging AdipoR2-deficient mice are hyperactive with enlarged brains excessively rich in saturated fatty acids.

To investigate how the fatty acid composition of brain phospholipids influences brain-specific processes, we leveraged the AdipoR2 (adiponectin receptor 2) knockout mouse model in which the brain is enlarged, and cellular membranes are excessively rich in saturated fatty acids. Lipidomics analysis of brains at 2, 7, and 18 months of age showed that phosphatidylcholines, which make up about two-thirds of all cerebrum membrane lipids, contain a gross excess of saturated fatty acids in AdipoR2 knockout mice, and that this is mostly attributed to an excess palmitic acid (C16:0) at the expense of oleic acid (C18:1), consistent with a defect in fatty acid desaturation and elongation in the mutant. Specifically, there was a ~12% increase in the overall saturated fatty acid content within phosphatidylcholines and a ~30% increase in phosphatidylcholines containing two palmitic acids. Phosphatidylethanolamines, sphingomyelins, ceramides, lactosylceramides, and dihydroceramides also showed an excess of saturated fatty acids in the AdipoR2 knockout mice while nervonic acid (C24:1) was enriched at the expense of shorter saturated fatty acids in glyceroceramides. Similar defects were found in the cerebellum and myelin sheaths. Histology showed that cell density is lower in the cerebrum of AdipoR2 knockout mice, but electron microscopy did not detect reproducible defects in the ultrastructure of cerebrum neurons, though proteomics analysis showed an enrichment of electron transport chain proteins in the cerebellum. Behavioral tests showed that older (33 weeks old) AdipoR2 knockout mice are hyperactive and anxious compared to control mice of a similar age. Also, in contrast to control mice, the AdipoR2 knockout mice do not gain weight in old age but do have normal lifespans. We conclude that an excess fatty acid saturation in brain phospholipids is accompanied by hyperactivity but seems otherwise well tolerated.

Gastroparesis for the nongastroenterologist.

Gastroparesis is a heterogeneous motility disorder characterized by nausea, vomiting, and postprandial fullness. Its diagnosis requires objective documentation of delayed gastric emptying of solid food and exclusion of mechanical obstruction. Its epidemiology is unclear, and the main causes are diabetes mellitus and idiopathic disease. Cardinal symptoms often co-occur. Management involves nutritional assessment, dietary changes, drug evaluation, glycemic control (for patients with diabetes mellitus), and symptom relief. In this review, we explore challenges nongastroenterologists may encounter and how they can use current recommendations to manage patients with gastroparesis.

Unearthing the soil-borne microbiome of land plants.

Plant-soil biodiversity interactions are fundamental for the functioning of terrestrial ecosystems. Yet, the existence of a set of globally distributed topsoil microbial and small invertebrate organisms consistently associated with land plants (i.e., their consistent soil-borne microbiome), together with the environmental preferences and functional capabilities of these organisms, remains unknown. We conducted a standardized field survey under 150 species of land plants, including 58 species of bryophytes and 92 of vascular plants, across 124 locations from all continents. We found that, despite the immense biodiversity of soil organisms, the land plants evaluated only shared a small fraction (less than 1%) of all microbial and invertebrate taxa that were present across contrasting climatic and soil conditions and vegetation types. These consistent taxa were dominated by generalist decomposers and phagotrophs and their presence was positively correlated with the abundance of functional genes linked to mineralization. Finally, we showed that crossing environmental thresholds in aridity (aridity index of 0.65, i.e., the transition from mesic to dry ecosystems), soil pH (5.5; i.e., the transition from acidic to strongly acidic soils), and carbon (less than 2%, the lower limit of fertile soils) can result in drastic disruptions in the associations between land plants and soil organisms, with potential implications for the delivery of soil ecosystem processes under ongoing global environmental change.

Hotspots of biogeochemical activity linked to aridity and plant traits across global drylands.

Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in drylands, remain virtually unknown. Here we evaluated the relative importance of grazing pressure and herbivore type, climate and plant functional traits on 24 soil physical and chemical attributes that represent proxies of key ecosystem services related to decomposition, soil fertility, and soil and water conservation. To do this, we conducted a standardized global survey of 288 plots at 88 sites in 25 countries worldwide. We show that aridity and plant traits are the major factors associated with the magnitude of plant effects on fertile islands in grazed drylands worldwide. Grazing pressure had little influence on the capacity of plants to support fertile islands. Taller and wider shrubs and grasses supported stronger island effects. Stable and functional soils tended to be linked to species-rich sites with taller plants. Together, our findings dispel the notion that grazing pressure or herbivore type are linked to the formation or intensification of fertile islands in drylands. Rather, our study suggests that changes in aridity, and processes that alter island identity and therefore plant traits, will have marked effects on how perennial plants support and maintain the functioning of drylands in a more arid and grazed world.

Management of Acute Saddle Pulmonary Embolism in Pregnancy Following Fetal Surgery.

A 33-year-old gravidity three parity three (G3P3) woman at 34 weeks of pregnancy underwent fetal surgery to repair an open lumbosacral myelomeningocele at 22 weeks gestation and experienced preterm premature rupture of membranes as a result. She developed a saddle pulmonary embolus with signs of right heart strain while on prolonged bed rest. She was treated emergently with aspiration thrombectomy and suprarenal inferior vena cava (IVC) filter placement, followed by an uncomplicated cesarean delivery thereafter.

Virtual Reality Distraction for Reducing Acute Postoperative Pain After Hip Arthroplasty: A Randomized Trial.

BACKGROUND: Relaxation and distraction provided by virtual reality presentations might be analgesic and reduce the need for opioid analgesia. We tested the hypothesis that a virtual reality program (AppliedVR) decreases acute postoperative pain and opioid requirements in patients recovering from hip arthroplasty. We also evaluated whether virtual reality distraction improves patient mobility and reduces the need for antiemetics. METHODS: We evaluated 106 adults who were recovering from elective primary total hip arthroplasty. Participating patients were randomized to 2- to 8-minute-long 3-dimensional immersive virtual reality relaxation and distraction video presentations (eg, guided breathing exercises, games, mindfulness) or to 2-dimensional presentations of nature short films (eg, forest wildlife) with neutral music that was chosen to be neither overly relaxing nor distracting, presented through identical headsets. Our primary outcome was pain after virtual reality or sham video presentations, adjusted for pretreatment scores. Secondary outcomes included total opioid consumption, pain scores obtained per routine by nurse staff, perception of video system usability, and pain 1 week after hospital discharge. RESULTS: Fifty-two patients were randomized to virtual reality distraction and relaxation, and 54 were assigned to 2-dimensional sham presentations. Virtual reality presentations were not found to affect pain scores before and after presentations, with an estimated difference in means (virtual reality minus sham video) of -0.1 points (95% confidence interval [CI], -0.5 to 0.2; P = .391) on a 0 to 10 scale, with 10 being the worst. The mean (standard error [SE]) after-intervention pain score was estimated to be 3.4 (0.3) in the virtual reality group and 3.5 (0.2) in the reference group. Virtual reality treatment was not found to affect postoperative opioid consumption in morphine milligram equivalents, with an estimated ratio of geometric means (virtual reality/sham video) of 1.2 (95% CI, 0.6-2.1; P = .608). Virtual reality presentations were not found to reduce pain scores collected every 4 hours by nursing staff, with an estimated difference in means of 0.1 points (95% CI, -0.9 to 0.7; P = .768). CONCLUSIONS: We did not observe statistically significant or clinically meaningful reductions in average pain scores or opioid consumption. As used in our trial, virtual reality did not reduce acute postoperative pain.

Cognizant Fiber-Reinforced Polymer Composites Incorporating Seamlessly Integrated Sensing and Computing Circuitry.

Structural fiber-reinforced polymer (FRP) composite materials consisting of a polymer matrix reinforced with layers of high-strength fibers are used in numerous applications, including but not limited to spacecraft, vehicles, buildings, and bridges. Researchers in the past few decades have suggested the necessary integration of sensors (e.g., fiber optic sensors) in polymer composites to enable health monitoring of composites' performance over their service lives. This work introduces an innovative cognizant composite that can self-sense, compute, and implement decisions based on sensed values. It is a critical step towards smart, resilient infrastructure. We describe a method to fabricate textile sensors with flexible circuitry and a microcontroller within the polymer composite, enabling computational operations to take place in the composite without impacting its integrity. A microstructural investigation of the sensors showed that the amount of oxidative agent and soaking time of the fabric play a major role in the adsorption of polypyrrole (PPy) on fiberglass (FG). XPS results showed that the 10 g ferric chloride solution with 6 h of soaking time had the highest degree of protonation (28%) and, therefore, higher adsorption of PPy on FG. A strain range of 30% was achieved by examining different circuitry and sensor designs for their resistance and strain resolution under mechanical loading. A microcontroller was added to the circuit and then embedded within a composite material. This composite system was tested under flexural loading to demonstrate its self-sensing, computing, and actuation capabilities. The resulting cognizant composite demonstrated the ability to read resistance values and measure strain using the embedded microcontroller and autonomously actuate an LED light when the strain exceeds a predefined limit of 2000 µÎµ. The application of the proposed FRP system would provide in situ monitoring of structural composite components with autonomous response capabilities, as well as reduce manufacturing, production, and maintenance costs.

Genetic variation among elite inbred lines suggests potential to breed for BNI-capacity in maize.

Biological nitrification inhibition (BNI) is a plant function where root systems release antibiotic compounds (BNIs) specifically aimed at suppressing nitrifiers to limit soil-nitrate formation in the root zone. Little is known about BNI-activity in maize (Zea mays L.), the most important food, feed, and energy crop. Two categories of BNIs are released from maize roots; hydrophobic and hydrophilic BNIs, that determine BNI-capacity in root systems. Zeanone is a recently discovered hydrophobic compound with BNI-activity, released from maize roots. The objectives of this study were to understand/quantify the relationship between zeanone activity and hydrophobic BNI-capacity. We assessed genetic variability among 250 CIMMYT maize lines (CMLs) characterized for hydrophobic BNI-capacity and zeanone activity, towards developing genetic markers linked to this trait in maize. CMLs with high BNI-capacity and ability to release zeanone from roots were identified. GWAS was performed using 27,085 SNPs (with unique positions on the B73v.4 reference genome, and false discovery rate = 10), and phenotypic information for BNI-capacity and zeanone production from root systems. Eighteen significant markers were identified; three associated with specific BNI-activity (SBNI), four with BNI-activity per plant (BNIPP), another ten were common between SBNI and BNIPP, and one with zeanone release. Further, 30 annotated genes were associated with the significant SNPs; most of these genes are involved in pathways of "biological process", and one (AMT5) in ammonium regulation in maize roots. Although the inbred lines in this study were not developed for BNI-traits, the identification of markers associated with BNI-capacity suggests the possibility of using these genomic tools in marker-assisted selection to improve hydrophobic BNI-capacity in maize.

Differential responses to double-stranded RNA injection and feeding in Mormon cricket (Orthoptera: Tettigoniidae).

The Mormon cricket, Anabrus simplex, is a flightless katydid, one of the major devastating rangeland pests in several states of the western United States. During the past few years, their sudden and periodic outbreaks into massive migratory bands caused significant economic losses to the rangeland forage and agricultural crops, particularly grain crops. Current population management methods rely heavily on broad-spectrum chemical insecticides, which could be toxic to nontargets, and even the targeted species might develop resistance in the long run. Therefore, we assessed the potential of RNA interference (RNAi)-based alternative management strategies that could supplement the current methods. In insects, RNAi efficiency varies with the method of double-stranded RNA (dsRNA) delivery. We tested 2 different methods of dsRNA delivery: injection and oral feeding of dsRNA. The results showed that Mormon crickets are sensitive to injection of dsRNA in a dose-dependent manner, but refractory to the oral feeding of dsRNA. Further, we confirmed the high nuclease activity in the insect midgut. In order to protect the dsRNA from the dsRNase activity and facilitate its uptake in the midgut, we encapsulated dsRNA inside poly lactic-co-glycolic acid (PLGA) nanoparticles and studied its release kinetics and RNAi efficiency by oral feeding. The release kinetics clearly suggested that the PLGA nanoparticle permeates from the insect digestive system to the hemolymph; however, it failed to induce an efficient RNAi response of the targeted genes. In conclusion, our findings suggest the different responses to dsRNA delivery methods in Mormon crickets, and further investigations involving dsRNA stability and its uptake mechanism are required to use RNAi as an alternative Mormon cricket population management strategy.

The effect of intraoperative positive end expiratory pressure and tidal volume on postoperative acute kidney injury after orthopedic surgery.

BACKGROUND: To test whether higher intraoperative PEEP levels and/or higher TV levels are associated with higher incidence of postoperative AKI within the first postoperative week, in adult patients having orthopedic surgeries under general anesthesia. METHODS: We conducted a sub analysis of a non-randomized alternating intervention cross over study performed in patients undergoing orthopedic surgery under general anesthesia at Cleveland Clinic, Cleveland, OH. We included four different combinations of PEEP (5 or 8 cm H2 O) and TV (6 or 10 mL/kg of PBW) that alternated each week in the six orthopedic operating rooms. Our primary outcome was postoperative AKI defined by the KDIGO criteria with baseline creatinine as the closest preoperative value to the time of surgery obtained within 30 days and postoperative value as the highest creatinine value within 7 days after surgery. Secondary outcome was the maximum postoperative in-hospital creatinine level within seven postoperative days. MAIN RESULTS: A total of 1933 patients were included in the analysis. The incidence of AKI was 6.8% in the study population and similar in high TV versus low TV group and high PEEP versus low PEEP group. Neither TV nor PEEP significantly impacted AKI incidence. The estimated odds ratio of AKI comparing TV = 6 mL/kg to TV = 10 mL/kg was 0.96 (97.5% CI: 0.63, 1.46; p = .811); while the estimated odds ratio of AKI comparing PEEP = 5cm H2 O to PEEP = 8cm H2 O was 0.92 (97.5% CI: 0.60, 1.39; p = .623). No interaction was found between TV and PEEP on AKI. Additionally, neither TV nor PEEP had a significant effect on the seven postoperative day creatinine levels. CONCLUSION: Higher levels of PEEP or TV during mechanical ventilation in adult patients undergoing orthopedic surgeries under general anesthesia do not increase the odds of developing postoperative AKI within the narrow limits studied.

Generalizability of nociception level as a measure of intraoperative nociceptive stimulation: A retrospective analysis.

BACKGROUND: Nociception-guided intraoperative opioid administration might help reduce postoperative pain. A commonly used and validated nociception monitor system is nociception level (NOL), which provides the nociception index, ranging from 0 to 100, with 0 representing no nociception and 100 representing extreme nociception. We tested the hypothesis that NOL responses are similar in men and women given remifentanil and fentanyl, across various types of anesthesia, as a function of American Society of Anesthesiologists physical status designations, and over a range of ages and body morphologies. METHODS: We conducted a retrospective cohort analysis of trial data from eight prospective NOL validation studies. Among 522 noncardiac surgical patients enrolled in these studies, 447 were included in our analysis. We assessed NOL responses to various noxious and non-noxious stimuli. RESULTS: The average NOL in response to 315 noxious stimuli was 47 ± 15 (95% CI = 45-49). The average NOL in response to 361 non-noxious stimuli was 10 ± 12 (95% CI = 9-11). NOL responses were similar in men and women, in patients given remifentanil and fentanyl, across various types of anesthesia, as a function of American Society of Anesthesiologists physical status designations, and over a range of ages and body morphologies. CONCLUSION: Nociception level appears to provide accurate estimates of intraoperative nociception over a broad range of patients and anesthetic conditions.

Soil contamination in nearby natural areas mirrors that in urban greenspaces worldwide.

Soil contamination is one of the main threats to ecosystem health and sustainability. Yet little is known about the extent to which soil contaminants differ between urban greenspaces and natural ecosystems. Here we show that urban greenspaces and adjacent natural areas (i.e., natural/semi-natural ecosystems) shared similar levels of multiple soil contaminants (metal(loid)s, pesticides, microplastics, and antibiotic resistance genes) across the globe. We reveal that human influence explained many forms of soil contamination worldwide. Socio-economic factors were integral to explaining the occurrence of soil contaminants worldwide. We further show that increased levels of multiple soil contaminants were linked with changes in microbial traits including genes associated with environmental stress resistance, nutrient cycling, and pathogenesis. Taken together, our work demonstrates that human-driven soil contamination in nearby natural areas mirrors that in urban greenspaces globally, and highlights that soil contaminants have the potential to cause dire consequences for ecosystem sustainability and human wellbeing.

Dual role of Apolipoprotein D as long-term instructive factor and acute signal conditioning microglial secretory and phagocytic responses.

Microglial cells are recognized as very dynamic brain cells, screening the environment and sensitive to signals from all other cell types in health and disease. Apolipoprotein D (ApoD), a lipid-binding protein of the Lipocalin family, is required for nervous system optimal function and proper development and maintenance of key neural structures. ApoD has a cell and state-dependent expression in the healthy nervous system, and increases its expression upon aging, damage or neurodegeneration. An extensive overlap exists between processes where ApoD is involved and those where microglia have an active role. However, no study has analyzed the role of ApoD in microglial responses. In this work, we test the hypothesis that ApoD, as an extracellular signal, participates in the intercellular crosstalk sensed by microglia and impacts their responses upon physiological aging or damaging conditions. We find that a significant proportion of ApoD-dependent aging transcriptome are microglia-specific genes, and show that lack of ApoD in vivo dysregulates microglial density in mouse hippocampus in an age-dependent manner. Murine BV2 and primary microglia do not express ApoD, but it can be internalized and targeted to lysosomes, where unlike other cell types it is transiently present. Cytokine secretion profiles and myelin phagocytosis reveal that ApoD has both long-term pre-conditioning effects on microglia as well as acute effects on these microglial immune functions, without significant modification of cell survival. ApoD-triggered cytokine signatures are stimuli (paraquat vs. Aß oligomers) and sex-dependent. Acute exposure to ApoD induces microglia to switch from their resting state to a secretory and less phagocytic phenotype, while long-term absence of ApoD leads to attenuated cytokine induction and increased myelin uptake, supporting a role for ApoD as priming or immune training factor. This knowledge should help to advance our understanding of the complex responses of microglia during aging and neurodegeneration, where signals received along our lifespan are combined with damage-triggered acute signals, conditioning both beneficial roles and limitations of microglial functions.

Soil biodiversity supports the delivery of multiple ecosystem functions in urban greenspaces.

While the contribution of biodiversity to supporting multiple ecosystem functions is well established in natural ecosystems, the relationship of the above- and below-ground diversity with ecosystem multifunctionality remains virtually unknown in urban greenspaces. Here we conducted a standardized survey of urban greenspaces from 56 municipalities across six continents, aiming to investigate the relationships of plant and soil biodiversity (diversity of bacteria, fungi, protists and invertebrates, and metagenomics-based functional diversity) with 18 surrogates of ecosystem functions from nine ecosystem services. We found that soil biodiversity across biomes was significantly and positively correlated with multiple dimensions of ecosystem functions, and contributed to key ecosystem services such as microbially driven carbon pools, organic matter decomposition, plant productivity, nutrient cycling, water regulation, plant-soil mutualism, plant pathogen control and antibiotic resistance regulation. Plant diversity only indirectly influenced multifunctionality in urban greenspaces via changes in soil conditions that were associated with soil biodiversity. These findings were maintained after controlling for climate, spatial context, soil properties, vegetation and management practices. This study provides solid evidence that conserving soil biodiversity in urban greenspaces is key to supporting multiple dimensions of ecosystem functioning, which is critical for the sustainability of urban ecosystems and human wellbeing.

The global distribution and environmental drivers of the soil antibiotic resistome.

BACKGROUND: Little is known about the global distribution and environmental drivers of key microbial functional traits such as antibiotic resistance genes (ARGs). Soils are one of Earth's largest reservoirs of ARGs, which are integral for soil microbial competition, and have potential implications for plant and human health. Yet, their diversity and global patterns remain poorly described. Here, we analyzed 285 ARGs in soils from 1012 sites across all continents and created the first global atlas with the distributions of topsoil ARGs. RESULTS: We show that ARGs peaked in high latitude cold and boreal forests. Climatic seasonality and mobile genetic elements, associated with the transmission of antibiotic resistance, were also key drivers of their global distribution. Dominant ARGs were mainly related to multidrug resistance genes and efflux pump machineries. We further pinpointed the global hotspots of the diversity and proportions of soil ARGs. CONCLUSIONS: Together, our work provides the foundation for a better understanding of the ecology and global distribution of the environmental soil antibiotic resistome. Video Abstract.

The time course of behavioural phase change in the Central American locust Schistocerca piceifrons.

Locusts exhibit an extreme form of phenotypic plasticity and can exist as two alternative phenotypes, known as solitarious and gregarious phases. These phases, which can transform from one to another depending on local population density, show distinctly different behavioural characteristics. The proximate mechanisms of behavioural phase polyphenism have been well studied in the desert locust Schistocerca gregaria and the migratory locust Locusta migratoria, and what is known in these species is often treated as a general feature of locusts. However, this approach might be flawed, given that there are approximately 20 locust species that have independently evolved phase polyphenism. Using the Central American locust Schistocerca piceifrons as a study system, we characterised the time course of behavioural phase change using standard locust behavioural assays, using both a logistic regression-based model and analyses of separate behavioural variables. We found that for nymphs of S. piceifrons, solitarisation was a relatively fast, two-step process, but that gregarisation was a much slower process. Additionally, the density of the gregarisation treatment seemed to have no effect on the rate of phase change. These data are at odds with what we know about the time course of behavioural phase change in S. gregaria, suggesting that the mechanisms of locust phase polyphenism in these two species are different and may not be phylogenetically constrained. Our study represents the most in-depth study of behavioural gregarisation and solitarisation in locusts to date.

Global hotspots for soil nature conservation.

Soils are the foundation of all terrestrial ecosystems1. However, unlike for plants and animals, a global assessment of hotspots for soil nature conservation is still lacking2. This hampers our ability to establish nature conservation priorities for the multiple dimensions that support the soil system: from soil biodiversity to ecosystem services. Here, to identify global hotspots for soil nature conservation, we performed a global field survey that includes observations of biodiversity (archaea, bacteria, fungi, protists and invertebrates) and functions (critical for six ecosystem services) in 615 composite samples of topsoil from a standardized survey in all continents. We found that each of the different ecological dimensions of soils-that is, species richness (alpha diversity, measured as amplicon sequence variants), community dissimilarity and ecosystem services-peaked in contrasting regions of the planet, and were associated with different environmental factors. Temperate ecosystems showed the highest species richness, whereas community dissimilarity peaked in the tropics, and colder high-latitudinal ecosystems were identified as hotspots of ecosystem services. These findings highlight the complexities that are involved in simultaneously protecting multiple ecological dimensions of soil. We further show that most of these hotspots are not adequately covered by protected areas (more than 70%), and are vulnerable in the context of several scenarios of global change. Our global estimation of priorities for soil nature conservation highlights the importance of accounting for the multidimensionality of soil biodiversity and ecosystem services to conserve soils for future generations.