Dinuclear nitrido-bridged osmium complexes inhibit the mitochondrial calcium uniporter and protect cortical neurons against lethal oxygen-glucose deprivation.

Dysregulation of mitochondrial calcium uptake mediated by the mitochondrial calcium uniporter (MCU) is implicated in several pathophysiological conditions. Dinuclear ruthenium complexes are effective inhibitors of the MCU and have been leveraged as both tools to study mitochondrial calcium dynamics and potential therapeutic agents. In this study, we report the synthesis and characterization of Os245 ([Os(μ-N)(NH)Cl]) which is the osmium-containing analogue of our previously reported ruthenium-based inhibitor Ru265.

Warm Soil, Westerly Wind, and Wet Feet: Feeling and Measuring Ecological Time in the Roman World.

Although climate change, pollution, and environmental degradation are contemporary problems, these are also challenges with deep historic roots in antiquity. 2,000 years ago, during the Roman Climate Optimum, a period of unusually warm, wet, and stable temperatures in the Mediterranean from roughly 200 BCE to 150 CE, the Romans altered the natural environment so greatly that they produced a level of pollution that was unparalleled until the Industrial Revolution. It is precisely in this contradictory time of unusually productive growth and destruction that we discover a blossoming of textual and visual ecological calendars illustrating how the Romans experienced the changing Mediterranean seasons.

Ecological Calendars, Food Sovereignty, and Climate Adaptation in Standing Rock.

Indigenous food sovereignty relies on ecological knowledge of plants and animals, including knowledge related to their development and behavior through the seasons. In the context of anthropogenic climate change, ecological calendars based on Indigenous knowledge may enable communities to anticipate seasonal phenomena. We conducted research with communities in the Standing Rock Nation (North and South Dakota, USA) to develop ecological calendars based on their ecological knowledge.

Art and Environmental Struggle Curating an Exhibition About Place-Rooted Ecological Knowledge.

Inspired by ecological calendars, the Herbert F. Johnson Museum of Art organized the exhibition to coincide with the international conference , held at Cornell University in October 2021. The exhibition emphasized Indigenous ways of knowing and deployed the works of lesser-known artists from around the world to build greater understanding of and empathy for their communities' often overlooked histories and perspectives.

Simulation and analysis of lead-free perovskite solar cells incorporating cerium oxide as electron transporting layer.

The great demand for renewable energy has greatly contributed to the development of the solar cell industry. Recently, silicon solar cells have dominated the world market. The ease of processing gives perovskite solar cells (PSCs) an advantage over conventional silicon solar cells.

Improving the potential of ethyl acetate green anti-solvent to fabricate efficient and stable perovskite solar cells.

Until now, in all state-of-the-art efficient perovskite solar cells (PSCs), during the fabrication process of the perovskite layer, highly toxic anti-solvents such as toluene, chlorobenzene, and diethyl ether have been used. This is highly concerning and urgently needs to be considered by laboratories and institutes to protect the health of researchers and employees working towards safe PSC fabrication. Green anti-solvents are usually used along with low-performance PSCs.

Motif-based zwitterionic peptides impact their structure and immunogenicity.

The linkage of zwitterionic peptides containing alternating glutamic acid (E) and lysine (K) amino acids exhibits protective effects on protein drugs due to their high hydration capacity. Previously, short EK peptides covering the surface of a protein drug showed significant protective effects and low immunogenicity. However, for high-molecular-weight single-chain (HMWSC) zwitterionic peptides, the incorporation of structure-disrupting amino acids such as proline (P), serine (S), and glycine (G) is necessary to improve their protective ability.

Interpreting Ecological Calendars for the Public Through Exhibits, Art, and Education.

This article describes the process educators at Cornell Botanic Gardens undertook to interpret the Ecological Calendar research project for public audiences. An ecological calendar is a way of keeping track of seasonal changes in a habitat. Many communities use and have used such calendars to coordinate their subsistence activities based on these seasonal events.

Role of Biodiversity in Ecological Calendars and Its Implications for Food Sovereignty: Empirical Assessment of the Resilience of Indicator Species to Anthropogenic Climate Change.

Ecological calendars are knowledge systems based on close observation of one's habitat to measure and give meaning to time, thereby providing anticipatory capacity for livelihood activities and contributing to food sovereignty. They rely upon seasonal indicators that integrate biophysical and ecological phenomena (e.g.

Surface Ocean Biogeochemistry Regulates the Impact of Anthropogenic Aerosol Fe Deposition on the Cycling of Iron and Iron Isotopes in the North Pacific.

Distinctively-light isotopic signatures associated with Fe released from anthropogenic activity have been used to trace basin-scale impacts. However, this approach is complicated by the way Fe cycle processes modulate oceanic dissolved Fe (dFe) signatures (δFe) post deposition. Here we include dust, wildfire, and anthropogenic aerosol Fe deposition in a global ocean biogeochemical model with active Fe isotope cycling, to quantify how anthropogenic Fe impacts surface ocean dFe and δFe.

Dust, Sand, and Winds Within an Active Martian Storm in Jezero Crater.

Rovers and landers on Mars have experienced local, regional, and planetary-scale dust storms. However, in situ documentation of active lifting within storms has remained elusive. Over 5-11 January 2022 (L 153°-156°), a dust storm passed over the Perseverance rover site.

Developing a rational approach to designing recombinant proteins for peptide-directed nanoparticle synthesis.

The controlled formation of nanoparticles with optimum characteristics and functional aspects has proven successful peptide-mediated nanoparticle synthesis. However, the effects of the peptide sequence and binding motif on surface features and physicochemical properties of nanoparticles are not well-understood. In this study, we investigate in a comparative manner how a specific peptide known as Pd4 and its two known variants may form nanoparticles both in an isolated state and when attached to a green fluorescent protein (GFPuv).

Investigation of ion-electrode interactions of linear polyimides and alkali metal ions for next generation alternative-ion batteries.

Organic electrode materials offer unique opportunities to utilize ion-electrode interactions to develop diverse, versatile, and high-performing secondary batteries, particularly for applications requiring high power densities. However, a lack of well-defined structure-property relationships for redox-active organic materials restricts the advancement of the field. Herein, we investigate a family of diimide-based polymer materials with several charge-compensating ions (Li, Na, K) in order to systematically probe how redox-active moiety, ion, and polymer flexibility dictate their thermodynamic and kinetic properties.

Weed germinable seedbanks of rice-wheat systems in the Eastern Indo-Gangetic Plains: Do tillage and edaphic factors explain community variation?

Zero tillage (ZT) is widely promoted throughout India's Eastern Indo-Gangetic Plains (IGP) because of its potential to increase wheat productivity and resilience to abiotic stresses. Weeds remain a major barrier to ZT adoption, yet it remains unclear how ZT will influence weed communities in the Eastern-IGP. The primary objective of this study was to characterise the composition of the germinable weed seedbank sampled just prior to the wheat phase of rice-wheat farms in Bihar and Eastern Uttar Pradesh, and examine whether adoption of ZT wheat has shifted weed community composition compared to conventional tillage (CT).

Opportunities for the conservation of migratory birds to benefit threatened resident vertebrates in the Neotropics.

Neotropical countries receive financing and effort from temperate nations to aid the conservation of migratory species that move between temperate and tropical regions. If allocated strategically, these resources could simultaneously contribute to other conservation initiatives. In this study, we use novel distribution maps to show how those resources could aid planning for the recovery of threatened resident vertebrates.

Improved Parameterization for the Size Distribution of Emitted Dust Aerosols Reduces Model Underestimation of Super Coarse Dust.

Aircraft measurement campaigns have revealed that super coarse dust (diameter >10 μm) surprisingly accounts for approximately a quarter of aerosols by mass in the atmosphere. However, most global aerosol models either underestimate or do not include super coarse dust abundance. To address this problem, we use brittle fragmentation theory to develop a parameterization for the emitted dust size distribution that includes emission of super coarse dust.

Orbital and In-Situ Investigation of Periodic Bedrock Ridges in Glen Torridon, Gale Crater, Mars.

Gale crater, the field site for NASA's Mars Science Laboratory Curiosity rover, contains a diverse and extensive record of aeolian deposition and erosion. This study focuses on a series of regularly spaced, curvilinear, and sometimes branching bedrock ridges that occur within the Glen Torridon region on the lower northwest flank of Aeolis Mons, the central mound within Gale crater. During Curiosity's exploration of Glen Torridon between sols ∼2300-3080, the rover drove through this field of ridges, providing the opportunity for in situ observation of these features.

InSight Pressure Data Recalibration, and Its Application to the Study of Long-Term Pressure Changes on Mars.

Observations of the South Polar Residual Cap suggest a possible erosion of the cap, leading to an increase of the global mass of the atmosphere. We test this assumption by making the first comparison between Viking 1 and InSight surface pressure data, which were recorded 40 years apart. Such a comparison also allows us to determine changes in the dynamics of the seasonal ice caps between these two periods.

The High-Frequency Signature of Slow and Fast Laboratory Earthquakes.

Tectonic faults fail through a spectrum of slip modes, ranging from slow aseismic creep to rapid slip during earthquakes. Understanding the seismic radiation emitted during these slip modes is key for advancing earthquake science and earthquake hazard assessment. In this work, we use laboratory friction experiments instrumented with ultrasonic sensors to document the seismic radiation properties of slow and fast laboratory earthquakes.

Fluvial Depositional Systems of the African Humid Period: An Analog for an Early, Wet Mars in the Eastern Sahara.

A widely hypothesized but complex transition from widespread fluvial activity to predominantly aeolian processes is inferred on Mars based on remote sensing data observations of ancient landforms. However, the lack of analysis of in situ martian fluvial deposits hinders our understanding of the flow regime nature and sustainability of the martian fluvial activity and the hunt for ancient life. Studying analogs from arid zones on Earth is fundamental to quantitatively understanding geomorphic processes and climate drivers that might have dominated during early Mars.

Soil Thermophysical Properties Near the InSight Lander Derived From 50 Sols of Radiometer Measurements.

Measurements from the InSight lander radiometer acquired after landing are used to characterize the thermophysical properties of the Martian soil in Homestead hollow. This data set is unique as it stems from a high measurement cadence fixed platform studying a simple well-characterized surface, and it benefits from the environmental characterization provided by other instruments. We focus on observations acquired before the arrival of a regional dust storm (near Sol 50), on the furthest observed patch of soil (i.

Development of a NanoBRET assay to validate inhibitors of Sirt2-mediated lysine deacetylation and defatty-acylation that block prostate cancer cell migration.

Sirtuin2 (Sirt2) with its NAD-dependent deacetylase and defatty-acylase activities plays a central role in the regulation of specific cellular functions. Dysregulation of Sirt2 activity has been associated with the pathogenesis of many diseases, thus making Sirt2 a promising target for pharmaceutical intervention. Herein, we present new high affinity Sirt2 selective Sirtuin-Rearranging Ligands (SirReals) that inhibit both Sirt2-dependent deacetylation and defatty-acylation and in cells.

Monitoring the heme iron state in horseradish peroxidase to detect ultratrace amounts of hydrogen peroxide in alcohols.

Despite the importance of hydrogen peroxide (HO) in initiating oxidative damage and its connection to various diseases, the detection of low concentrations of HO (<10 μM) is still limited using current methods, particularly in non-aqueous systems. One of the most common methods is based on examining the color change of a reducing substrate upon oxidation using UV/Vis spectrophotometry, fluorophotometry and/or paper test strips. In this study, we show that this method encounters low efficiency and sensitivity for detection of ultratrace amounts of HO in non-aqueous media.

Trapping and structural characterisation of a covalent intermediate in vitamin B biosynthesis catalysed by the Pdx1 PLP synthase.

The Pdx1 enzyme catalyses condensation of two carbohydrates and ammonia to form pyridoxal 5-phosphate (PLP) an imine relay mechanism of carbonyl intermediates. The I intermediate characterised here using structural, UV-vis absorption spectroscopy and mass spectrometry analyses rationalises stereoselective deprotonation and subsequent substrate assisted phosphate elimination, central to PLP biosynthesis.