A telescopic paradox: the artisans of the Accademia del Cimento, their instruments and their (in)visibility.

The brief life of the Accademia del Cimento (1657-1667), the first known society with a purely experimental programme, is entangled with the most surprising advancements in the history of scientific instruments of that century, from the telescope to the microscope, the thermometer to the barometer, the hygrometer to the pendulum as a time-regulator, and more. The making of instruments at the Florentine court shows the interaction of princely, scholarly and artisanal actors. This paper explores this collaboration and shows how the supposed "invisibility' of artisans depended on their proximity to the academicians and princes, who mainly communicated verbally with them, directly or through middlemen.

Total synthesis of (-)-scabrolide A and (-)-yonarolide.

The complete account of the total syntheses of scabrolide A and yonarolide is disclosed. This article describes an initial approach involving a bio-inspired macrocyclization/transannular Diels-Alder cascade, which ultimately failed due to undesired reactivity during macrocycle construction. Next, the evolution of a second and third strategy, which both involve an initial intramolecular Diels-Alder reaction followed by a late-stage closure of the seven-membered ring of scabrolide A are detailed.

A convergent fragment coupling strategy to access quaternary stereogenic centers.

The formation of quaternary stereogenic centers convergent fragment coupling is a longstanding challenge in organic synthesis. Here, we report a strategy for the formation of quaternary stereogenic centers in polycyclic systems based upon the semi-pinacol reaction. In the key transformation, two fragments of a similar size and complexity are joined by a 1,2-addition of an alkenyl lithium to an epoxy ketone, and the resulting epoxy silyl ether undergoes a semi-pinacol rearrangement catalyzed by -(trimethylsilyl)bis(trifluoromethanesulfonyl)imide (TMSNTf) or trimethylsilyl trifluoromethanesulfonate (TMSOTf).

Enantio- and Diastereoenriched Enzymatic Synthesis of 1,2,3-Polysubstituted Cyclopropanes from (Z/E)-Trisubstituted Enol Acetates.

In nature and synthetic chemistry, stereoselective [2+1] cyclopropanation is the most prevalent strategy for the synthesis of chiral cyclopropanes, a class of key pharmacophores in pharmaceuticals and bioactive natural products. One of the most extensively studied reactions in the organic chemist's arsenal, stereoselective [2+1] cyclopropanation, largely relies on the use of stereodefined olefins, which require elaborate laboratory synthesis or tedious separation to ensure high stereoselectivity. Here we report engineered hemoproteins derived from a bacterial cytochrome P450 that catalyze the synthesis of chiral 1,2,3-polysubstituted cyclopropanes, regardless of the stereopurity of the olefin substrates used.

A Reevaluation of Cryolava Flow Evolution: Assumptions, Physical Properties, and Conceptualization.

Cryovolcanism has been invoked to explain numerous features observed on icy bodies. Many of these features show similar morphologies to volcanic features observed on Earth suggesting similar physics involved in their formation. Cryovolcanism lies at the intersection of volcanology and hydrology but as such, no one model from either discipline satisfactorily represents cryolava flow emplacement.

The Curiosity Rover's Exploration of Glen Torridon, Gale Crater, Mars: An Overview of the Campaign and Scientific Results.

The Mars Science Laboratory rover, , explored the clay mineral-bearing Glen Torridon region for 1 Martian year between January 2019 and January 2021, including a short campaign onto the Greenheugh pediment. The Glen Torridon campaign sought to characterize the geology of the area, seek evidence of habitable environments, and document the onset of a potentially global climatic transition during the Hesperian era. roved 5 km in total throughout Glen Torridon, from the Vera Rubin ridge to the northern margin of the Greenheugh pediment.

Compositions and Interior Structures of the Large Moons of Uranus and Implications for Future Spacecraft Observations.

The five large moons of Uranus are important targets for future spacecraft missions. To motivate and inform the exploration of these moons, we model their internal evolution, present-day physical structures, and geochemical and geophysical signatures that may be measured by spacecraft. We predict that if the moons preserved liquid until present, it is likely in the form of residual oceans less than 30 km thick in Ariel, Umbriel, and less than 50 km in Titania, and Oberon.

Mars 2020 Perseverance Rover Studies of the Martian Atmosphere Over Jezero From Pressure Measurements.

The pressure sensors on Mars rover Perseverance measure the pressure field in the Jezero crater on regular hourly basis starting in sol 15 after landing. The present study extends up to sol 460 encompassing the range of solar longitudes from  ∼ 13°-241° (Martian Year (MY) 36). The data show the changing daily pressure cycle, the sol-to-sol seasonal evolution of the mean pressure field driven by the CO sublimation and deposition cycle at the poles, the characterization of up to six components of the atmospheric tides and their relationship to dust content in the atmosphere.

The Development and Demonstration of the Portable Acousto-Optic Spectrometer for Astrobiology in Cave Environments.

Planetary caves are desirable environments for the search for biosignatures corresponding to extant or extinct extraterrestrial life due to the protection they offer from surface-level solar radiation and ionizing particles. Near-infrared (NIR) reflectance spectroscopy is one of a multitude of techniques that, when taken together, can provide a comprehensive understanding of the geomicrobiology in planetary subsurface regions. To that end, we developed two portable NIR spectrometers that employ acousto-optic tunable filters and demonstrated them in three geochemically distinct cave environments.

Lifting and Transport of Martian Dust by the Ingenuity Helicopter Rotor Downwash as Observed by High-Speed Imaging From the Perseverance Rover.

Martian atmospheric dust is a major driver of weather, with feedback between atmospheric dust distribution, circulation changes from radiative heating and cooling driven by this dust, and winds that mobilize surface dust and distribute it in the atmosphere. Wind-driven mobilization of surface dust is a poorly understood process due to significant uncertainty about minimum wind stress and whether the saltation of sand particles is required. This study utilizes video of six Ingenuity helicopter flights to measure dust lifting during helicopter ascents, traverses, and descents.

Winds at the Mars 2020 Landing Site. 2. Wind Variability and Turbulence.

Wind speeds measured by the Mars 2020 Perseverance rover in Jezero crater were fitted as a Weibull distribution. InSight wind data acquired in Elysium Planitia were also used to contextualize observations. Jezero winds were found to be much calmer on average than in previous landing sites, despite the intense aeolian activity observed.

Observations of a Solar Energetic Particle Event From Inside and Outside the Coma of Comet 67P.

We analyze observations of a solar energetic particle (SEP) event at Rosetta's target comet 67P/Churyumov-Gerasimenko during 6-10 March 2015. The comet was 2.15 AU from the Sun, with the Rosetta spacecraft approximately 70 km from the nucleus placing it deep inside the comet's coma and allowing us to study its response.

Influence of patient-specific factors when comparing multifidus fat infiltration between chronic low back pain patients and asymptomatic controls.

Introduction: Many studies have attempted to link multifidus (MF) fat infiltration with muscle quality and chronic low back pain (cLBP), but there is no consensus on these relationships.

Methods: In this cross-sectional cohort study, 39 cLBP patients and 18 asymptomatic controls were included. The MF muscle was manually segmented at each lumbar disc level and fat fraction (FF) measurements were taken from the corresponding advanced imaging water-fat images.

Marsquake Locations and 1-D Seismic Models for Mars From InSight Data.

We present inversions for the structure of Mars using the first Martian seismic record collected by the InSight lander. We identified and used arrival times of direct, multiples, and depth phases of body waves, for 17 marsquakes to constrain the quake locations and the one-dimensional average interior structure of Mars. We found the marsquake hypocenters to be shallower than 40 km depth, most of them being located in the Cerberus Fossae graben system, which could be a source of marsquakes.

Global Variations in Water Vapor and Saturation State Throughout the Mars Year 34 Dusty Season.

To understand the evolving martian water cycle, a global perspective of the combined vertical and horizontal distribution of water is needed in relation to supersaturation and water loss and how it varies spatially and temporally. The global vertical water vapor distribution is investigated through an analysis that unifies water, temperature and dust retrievals from several instruments on multiple spacecraft throughout Mars Year (MY) 34 with a global circulation model. During the dusty season of MY 34, northern polar latitudes are largely absent of water vapor below 20 km with variations above this altitude due to transport from mid-latitudes during a global dust storm, the downwelling branch of circulation during perihelion season and the intense MY 34 southern summer regional dust storm.

Wind-Induced Variability of Warm Water on the Southern Bellingshausen Sea Continental Shelf.

The Bellingshausen Sea hosts heat transport onto the continental shelf, potentially enhancing ice shelf basal melt. Here, we use the GLORYS12V1 1993-2018 reanalysis to identify physical processes that set seasonal and interannual variability of water mass properties in the Eltanin and Latady Bays on the southern Bellingshausen Sea continental shelf. Annual means of potential temperature from 300 m to the seabed reveal interannual variability and allow separation into warm and cold regimes.

Water and Chlorine in the Martian Subsurface Along the Traverse of NASA's Curiosity Rover: 1. DAN Measurement Profiles Along the Traverse.

This paper presents estimates of the water and chlorine contents in the subsurface of Gale crater based on the measurements by the Dynamic Albedo of Neutrons (DAN) instrument onboard the NASA Curiosity rover. It is Part 1 of a two-paper series. Data derived both from DAN active and passive measurements are presented in discrete surface areas (pixels) assuming a homogeneous distribution of water within the DAN sensing depth (60 cm) along the traverse of the rover.

Autonomous CE Mass-Spectra Examination for the Ocean Worlds Life Surveyor.

Ocean worlds such as Europa and Enceladus are high priority targets in the search for past or extant life beyond Earth. Evidence of life may be preserved in samples of surface ice by processes such as deposition from active plumes, hydrofracturing, or thermal convection. Terrestrial life produces unique distributions of organic molecules that translate into recognizable biosignatures.

Risk prediction model of peritoneal seeding in advanced gastric cancer: A decision tool for diagnostic laparoscopy.

Background: Selective diagnostic laparoscopy in gastric cancer patients at high risk of peritoneal metastasis is essential for optimal treatment planning. In this study available clinicopathologic factors predictive of peritoneal seeding in advanced gastric cancer (AGC) were identified, and this information was translated into a clinically useful tool.

Methods: Totally 2833 patients underwent surgery for AGC between 2003 and 2013.

Optimizing Earthquake Nowcasting With Machine Learning: The Role of Strain Hardening in the Earthquake Cycle.

Nowcasting is a term originating from economics, finance, and meteorology. It refers to the process of determining the uncertain state of the economy, markets or the weather at the current time by indirect means. In this paper, we describe a simple two-parameter data analysis that reveals hidden order in otherwise seemingly chaotic earthquake seismicity.

In Situ Regolith Seismic Velocity Measurement at the InSight Landing Site on Mars.

Interior exploration using Seismic Investigations, Geodesy and Heat Transport's (InSight) seismometer package Seismic Experiment for Interior Structure (SEIS) was placed on the surface of Mars at about 1.2 m distance from the thermal properties instrument Heat flow and Physical Properties Package (HP) that includes a self-hammering probe. Recording the hammering noise with SEIS provided a unique opportunity to estimate the seismic wave velocities of the shallow regolith at the landing site.

State-resolved infrared spectrum of the protonated water dimer: revisiting the characteristic proton transfer doublet peak.

The infrared (IR) spectra of protonated water clusters encode precise information on the dynamics and structure of the hydrated proton. However, the strong anharmonic coupling and quantum effects of these elusive species remain puzzling up to the present day. Here, we report unequivocal evidence that the interplay between the proton transfer and the water wagging motions in the protonated water dimer (Zundel ion) giving rise to the characteristic doublet peak is both more complex and more sensitive to subtle energetic changes than previously thought.

Intrinsic Dimensionality as a Metric for the Impact of Mission Design Parameters.

High-resolution space-based spectral imaging of the Earth's surface delivers critical information for monitoring changes in the Earth system as well as resource management and utilization. Orbiting spectrometers are built according to multiple design parameters, including ground sampling distance (GSD), spectral resolution, temporal resolution, and signal-to-noise ratio. Different applications drive divergent instrument designs, so optimization for wide-reaching missions is complex.