Dung predicts the global distribution of herbivore grazing pressure in drylands
Related Articles
Measurement of phospholipid lateral diffusion at high pressure by in situ magic-angle spinning NMR spectroscopy
The development of experimental methodologies that enable investigations of biochemistry at high pressure promises to yield significant advances in our understanding of life on Earth and its origins. Here, we introduce a method for studying lipid membranes at thermodynamic conditions relevant for life at deep sea hydrothermal vents. Using in situ high pressure magic-angle spinning solid state nuclear magnetic resonance spectroscopy (NMR), we measure changes in the fluidity of model microbial membranes at pressures up to 28 MPa. We find that the fluid-phase lateral diffusion of phospholipids at high pressure is significantly affected by the stoichiometric ratio of lipids in the membrane. Our results were facilitated by an accessible pressurization strategy that we have developed to enable routine preparation of solid state NMR rotors to pressures of 30 MPa or greater.
Coastal wetland resilience through local, regional and global conservation
Coastal wetlands, including tidal marshes, mangrove forests and tidal flats, support the livelihoods of millions of people. Understanding the resilience of coastal wetlands to the increasing number and intensity of anthropogenic threats (such as habitat conversion, pollution, fishing and climate change) can inform what conservation actions will be effective. In this Review, we synthesize anthropogenic threats to coastal wetlands and their resilience through the lens of scale. Over decades and centuries, anthropogenic threats have unfolded across local, regional and global scales, reducing both the extent and quality of coastal wetlands. The resilience of existing coastal wetlands is driven by their quality, which is modulated by both physical conditions (such as sediment supply) and ecological conditions (such as species interactions operating from local through to global scales). Protection and restoration efforts, however, are often localized and focus on the extent of coastal wetlands. The future of coastal wetlands will depend on an improved understanding of their resilience, and on society’s actions to enhance both their extent and quality across different scales.
Blood pressure elevations post-lenvatinib treatment in hepatocellular carcinoma: a potential marker for better prognosis
Lenvatinib is a tyrosine kinase inhibitor that effectively inhibits vascular endothelial growth factor signaling and is used for treating hepatocellular carcinoma. However, angiogenesis inhibitors often cause hypertension. Although lenvatinib-induced hypertension has been proposed as a potential surrogate marker for better prognosis, studies on blood pressure elevations and outcomes following lenvatinib initiation are limited. This study included 67 patients who underwent lenvatinib therapy at the Department of Gastroenterology, Kagoshima University Hospital, between May 2018 and December 2023. The median age of the cohort was 71 years, and 82.1% of the patients were male. The median blood pressure at admission was 128/73 mmHg, which significantly increased to 136/76 mmHg the day after lenvatinib administration. Grade 3 hypertension (≥160/100 mmHg) occurred in 37.3% of patients during hospitalization. The median increase in systolic blood pressure from admission to its peak during hospitalization was 26 mmHg. Patients who experienced an increase in blood pressure of ≥26 mmHg were classified into the blood pressure elevation group, which showed a significantly lower mortality rate than that of the blood pressure non-elevation group (35.3% vs. 81.8%, log-rank p = 0.007), even after adjusting for age, sex, disease stage, performance status, and liver reserve function. This study demonstrated that patients who experienced earlier blood pressure elevation after lenvatinib administration had lower overall mortality rates. These findings suggest that blood pressure elevations after lenvatinib initiation may serve as valuable prognostic indicators in patients with cancer undergoing lenvatinib therapy.
Metabolite-driven mechanisms reveal chemical ecology of Lehmann Lovegrass (Eragrostis lehmanniana) invasion in North American semi-arid ecosystems
Invasive plants threaten global ecosystems, yet traditional analyses of functional traits cannot fully explain their dominance over co-occurring natives. Metabolomics offers insights into plant invasions, but single-technique studies often miss critical biochemical mechanisms. We employ a multimodal metabolomics approach (¹H NMR, LC MS/MS, FT-ICR-MS, and MALDI-MSI) to investigate the biochemical basis of Lehmann lovegrass (Eragrostis lehmanniana) invasion in semi-arid North America, comparing it with a co-occurring native grass, Arizona cottontop (Digitaria californica). Our analysis reveals three metabolomic traits of Lehmann lovegrass compared to Arizona cottontop: Enhanced nitrogen allocation in shoots, reduced defensive metabolites in root layers; and increased root exudate modulation under stress conditions. These traits suggest Lehmann lovegrass succeeds through adaptation to increasing aridity rather than direct competition, demonstrating adaptation to nutrient-poor environments and high phenotypic plasticity in response to increasing aridity. This integrated metabolomic approach provides new mechanistic insights into invasion ecology and plant adaptation under environmental change.
Tuning a magnetic energy scale with pressure and field in UTe2
When a fragile ordered state is suppressed to zero temperature, a quantum phase transition occurs, which is often marked by the appearance of unconventional superconductivity. While the quantum critical point can be hidden, the influence of the quantum criticality extends to fairly high temperatures, manifesting non-Fermi liquid behavior in a wide range of the field-temperature-pressure phase space. Here, we report the tuning of a magnetic energy scale in the heavy-fermion superconductor UTe2, previously identified with a peak in the c-axis electrical transport temperature dependence, using applied hydrostatic pressures and a-axis-oriented magnetic fields as complementary (and opposing) tuning parameters: the characteristic peak in c-axis resistivity decreases in temperature with applied pressure before vanishing near the critical pressure of 15 kbar (1.5 GPa), while the application of field shifts the peak to a higher temperature and broadens it under all studied pressures. At the critical pressure, the transport behavior deviates from Fermi liquid behavior, exhibiting a nearly linear temperature dependence of resistivity with an enhanced pre-factor. Our results shed light on the microscopic origin of the c-axis resistivity peak and provide a clear picture of magnetic energy scale evolution relevant to quantum criticality in UTe2.
Responses