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The Venusian atmosphere hosts a 10 km deep convective layer that has been studied by various spacecrafts. However, the impact of the strong vertical mixing on the chemistry of this region is still unknown. This study presents the first realistic coupling between resolved small‐scale turbulence and a chemical network. The resulting vertical mixing is different for each species: those with longer chemical timescales will tend to be well‐mixed. Vertical eddy diffusion due to resolved convection motions was estimated, ranging from 102to 104m2/s for the 48–55 km convective layer, several orders of magnitude above the typically used value. In the 48–55 km convective layer, the impact of the small‐scale turbulence on the cloud layer boundaries was between 200 m and 1 km. The impact of turbulence on cloud chemistry is consistent with Venus Express/Visible and Infrared Thermal Imaging Spectrometer observations. The observability at the cloud‐top of small‐scale turbulence by VenSpec‐U spectrometer would be challenging. Venus hosts a global sulfuric acid cloud layer between 45 and 70 km. A convective layer is present between roughly 50 and 60 km, with its variability in latitude and local time assessed by observation, with a thicker layer at high latitude and at night. One question that remains unclear is how this turbulence mixes momentum, heat, and chemical species. Especially, the impact of the strong vertical mixing on the chemistry of this region is still unknown. To investigate this topic, we use a convection‐resolving model coupled for the first time with a realistic chemical network. The resulting vertical mixing is different for each species: those with longer chemical timescales will tend to be well‐mixed. 1D and global circulation models use the so‐called vertical eddy diffusion approach to represent turbulent motion, quantified in our model and underestimated in chemistry models. The small‐scale turbulence in the cloud layer causes a variation in the altitude of the top and bottom boundaries of the cloud. Our model shows that the impact of turbulence on cloud chemistry corresponds well to what has been observed by satellites. In the future, the EnVision mission will be able to observe chemical species at the small turbulence scales. Estimation for the first time of the spatial and temporal variability of chemical species due to vertical mixingQuantification of the vertical eddy diffusion coefficient, order of magnitude above typical used valuesCloud‐top altitudes change by 0.2–1 km due to vertical convective mixing and gravity waves Estimation for the first time of the spatial and temporal variability of chemical species due to vertical mixing Quantification of the vertical eddy diffusion coefficient, order of magnitude above typical used values Cloud‐top altitudes change by 0.2–1 km due to vertical convective mixing and gravity waves

Martian CO2ice clouds are intriguing features, representing a rare occurrence of atmospheric condensation of a major component. These clouds play a crucial role due to their radiative properties, interactions with surface, and coupling with microphysical cycles of aerosols. Observations have been limited, prompting modeling studies to understand their formation and dynamics. Here, we present the first high‐resolution 3D simulations of CO2ice clouds using a Large‐Eddy Simulation (LES) model incorporating CO2microphysics. We investigate cloud formation in idealized temperature perturbations in the polar night. A reference simulation with a −2K perturbation demonstrates that the formed CO2ice cloud possesses a convective potential, leading to its ascent in the troposphere. We determine the timescales and orders of magnitude of various phenomena involved in the lifecycle of a CO2ice cloud. Sensitivity tests show that convection can be inhibited or intensified by the thermodynamic and microphysical conditions of the simulated environment. CO2ice clouds have been observed in the Martian polar nights in the lower atmosphere. These clouds are extremely challenging to observe due to the lack of sunlight. However, they play a significant role in Mars' climate, especially through interactions with the surface and other atmospheric species. To study the formation processes of these clouds, we use a high‐resolution model. Even a relatively weak cooling can lead to the formation of a CO2ice cloud with convective potential, enabling it to move vertically upward. We determine the characteristic times and altitudes of this phenomenon and investigate how they respond when atmospheric parameters, such as cooling temperature, the presence of extra dust, or horizontal winds are varied. Our findings show that some of these parameters can either inhibit or enhance convection development. Coupling a convection model with a CO2microphysics scheme can simulate the formation of convective CO2ice clouds triggered by realistic perturbationsThese is a strong coupling between CO2ice cloud convection and dust cycle in the troposphereThe convective process intensity depends strongly on the number of available condensation nuclei and the temperature of the perturbation Coupling a convection model with a CO2microphysics scheme can simulate the formation of convective CO2ice clouds triggered by realistic perturbations These is a strong coupling between CO2ice cloud convection and dust cycle in the troposphere The convective process intensity depends strongly on the number of available condensation nuclei and the temperature of the perturbation

In JGR‐Planets, the peer review process is critical to ensuring that the published articles are based on sound scientific principles, follow state‐of‐the‐art techniques while acknowledging relevant prior results, and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. JGR‐Planetscovers a broad range of topics addressing every aspect of geoscience with the only requirement that the work addresses planetary processes. The wide breadth of topics published is reflected by our editorial team composed in 2023 of associate editors Adrian Brown, Jun Cui, Joel Davis, Leigh Fletcher, Matthias Grott, Ananya Mallik, Germán Martínez, Molly McCanta, Katarina Miljkovic, Naomi Murdoch, Ryan Park, Arianna Piccialli, Andrew Poppe, Beatrix Sánchez‐Cano, Laura Schaefer, Mariek Schmidt, Yasuhito Sekine, Kelsi Singer, Michael Sori, Norihiko Sugimoto, Sonia Tikoo, David Trang, and Zhiyong Xiao in addition to the editors who authored this note. We rely on the expertise of the community to vet the articles submitted to the journal. In 2023, JGR‐Planetsbenefited from 1,184 reviews provided by 731 unique volunteer referees. We also received help from 19 guest editors working on four active special collections. To these volunteers: We are truly grateful that you chose to dedicate your time and energy to evaluate manuscripts and to advise us on the suitability of each manuscript for JGR‐Planets, often suggesting ways to improve the papers. We know that all our volunteers juggle many duties, both professional and personal. On behalf of the entire editorial board of JGR‐Planets, we express our heartfelt gratitude to the many scientists who support this journal. Thank you! You are performing a valued service to this journal and to the community. The peer review process is the key to ensuring that the articles published in JGR‐Planetsare carefully vetted and present thoroughly considered, exciting discoveries or novel understandings of the fundamental processes that affect solar system objects. In 2023, JGR‐Planetsbenefitted from 1,184 reviews provided by 731 unique reviewers and from the help of 19 guest editors working on four active special collections. We are grateful that so many scientists chose to dedicate their time and energy to evaluating and suggesting ways to improve each submitted manuscript. We also wish to acknowledge our outstanding corps of 23 volunteer associate editors. Scientific publishing is truly a community effort. The entire editorial board of JGR‐Planetswishes to express our heartfelt gratitude to the many scientists who support this journal. Thank you! 731 referees provided 1,184 peer reviews of manuscripts in 2023The JGR‐PlanetsEditorial Board includes 23 volunteer associate editors who provide a crucial serviceThe peer review process is critical to the integrity of JGR‐Planets; the Editorial Board is appreciative of the efforts of these individuals 731 referees provided 1,184 peer reviews of manuscripts in 2023 The JGR‐PlanetsEditorial Board includes 23 volunteer associate editors who provide a crucial service The peer review process is critical to the integrity of JGR‐Planets; the Editorial Board is appreciative of the efforts of these individuals

Abstract

The atmosphere of Mars is thin, although rich in dust aerosols, and covers a dry surface. As such, Mars provides an opportunity to expand our knowledge of atmospheres beyond that attainable from the atmosphere of the Earth. The InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) lander is measuring Mars’s atmosphere with unprecedented continuity, accuracy and sampling frequency. Here we show that InSight unveils new atmospheric phenomena at Mars, especially in the higher-frequency range, and extends our understanding of Mars’s meteorology at all scales. InSight is uniquely sensitive to large-scale and regional weather and obtained detailed in situ coverage of a regional dust storm on Mars. Images have enabled high-altitude wind speeds to be measured and revealed airglow—faint emissions produced by photochemical reactions—in the middle atmosphere. InSight observations show a paradox of aeolian science on Mars: despite having the largest recorded Martian vortex activity and dust-devil tracks close to the lander, no visible dust devils have been seen. Meteorological measurements have produced a catalogue of atmospheric gravity waves, which included bores (soliton-like waves). From these measurements, we have discovered Martian infrasound and unexpected similarities between atmospheric turbulence on Earth and Mars. We suggest that the observations of Mars’s atmosphere by InSight will be key for prediction capabilities and future exploration.

Purpose: While aiming to create methods for fibre recycling, the question of colours in waste textiles is also in focus; whether the colour should be kept or should be removed while recycling textile fibre. More knowledge is needed for colour management in a circular economy approach. Design/methodology/approach: The research included the use of different dye types in a cotton dyeing process, the process for decolourizing and the results. Two reactive dyes, two direct dyes and one vat dye were used in the study. Four chemical treatment sequences were used to evaluate colour removal from the dyed cotton fabrics, namely, HCE-A, HCE-P-A, HCE-Z-P-A and HCE-Y-A. Findings: The objective was to evaluate how different chemical refining sequences remove colour from direct, reactive and vat dyed cotton fabrics, and how they influence the specific cellulose properties. Dyeing methods and the used refining sequences influence the degree of colour removal. The highest achieved final brightness of refined cotton materials were between 71 and 91 per cent ISO brightness, depending on the dyeing method used. Research limitations/implications: Only cotton fibre and three different colour types were tested. Practical implications: With cotton waste, it appears to be easier to remove the colour than to retain it, especially if the textile contains polyester residues, which are desired to be removed in the textile refining stage. Originality/value: Colour management in the CE context is an important new track to study in the context of the increasing amount of textile waste used as a raw material.

•What is the primary question addressed by this study?Is physical inactivity related differently to specific symptoms of depression, and are the associations bidirecional?•What is the main finding of this study?Most of the depressive symptoms showed temporal bidirectionanal association with physical inactivity, though the effects were generally small.The effects were stable with 2 and 4-year lags, suggesting that the effects reflect more direct association between relatively stable physical inactivity and individual depressive symptoms.•What is the meaning of the finding?Physical inactivity and depression seem to be bidirectionally associated even at symptom-level.

The conditions in Venus' upper mesosphere at around 120 km have some similarities to the upper mesosphere of Earth and Mars where ice clouds form. Here we show, using published satellite products and numerical modeling, that the upper mesosphere of Venus can be sufficiently cold that both H2O and CO2may condense to form particles. We show that amorphous solid water particles (ASW) are likely to nucleate both heterogeneously on meteoric smoke and also homogeneously, resulting in clouds of nano‐scaled particles at around 120 km that will occur globally. The temperatures may then become sufficiently low, below ∼90 K, that CO2particles can nucleate on ASW particles. Given the uncertainty associated with retrievals of temperature in the upper mesosphere, it is unclear how frequently this occurs, but it could be >30% of the time poleward of 60°. Since the main component of Venus' tenuous atmosphere is CO2, any CO2crystals that form will grow and sediment on a timescale of 10–20 min. Mie calculations show that these Venusian mesospheric clouds (VMCs) should be observable by contemporary satellite instruments, although their short lifetime means that the probability of detection is small. We suggest that VMCs are important for the redistribution of meteoric smoke and may serve as a cold‐trap, removing some water vapor from the very upper mesosphere of Venus through the growth and sedimentation of cloud particles, and possibly reducing the loss of water to space. Venus is renowned for extreme heat at the surface and clouds composed of sulfuric acid encircling the planet; however, there are regions of Venus's atmosphere that are sufficiently cold to harbor ice clouds. In fact, the temperatures frequently fall below 100 K at around 120 km altitude and under the right conditions, we have shown that ice clouds composed of both water and carbon dioxide ices can form. We have used published data from satellites that orbit Venus to show that clouds composed of nanometer sized water ice particles may encircle the planet. The temperatures are so low in this part of Venus' atmosphere that the ice in these water ice particles likely lacks any crystalline structure, i.e., it has an amorphous (liquid‐like) structure. Furthermore, if the temperature falls below about 90 K, we have shown that carbon dioxide ice crystals can form on top of water ice particles. Since the atmosphere of Venus is mainly made of carbon dioxide, these carbon dioxide crystals grow and then sediment rapidly in the thin atmosphere. If we were lucky enough to see one of these short‐lived sporadic clouds, it would look a bit like mares' tail cloud on Earth. The upper mesosphere of Venus can be supersaturated with respect to both amorphous solid water (ASW) and crystalline carbon dioxide iceThere is a persistent layer of nano‐scale ASW particles encircling VenusShort‐lived carbon dioxide ice clouds may sporadically form in the upper mesosphere The upper mesosphere of Venus can be supersaturated with respect to both amorphous solid water (ASW) and crystalline carbon dioxide ice There is a persistent layer of nano‐scale ASW particles encircling Venus Short‐lived carbon dioxide ice clouds may sporadically form in the upper mesosphere

We study a seasonally recurrent cyclone and related cloud phenomena observed on Mars at Ls~120°, latitude ~60°N, and longitude 90°W from images obtained with cameras in different spacecraft between 1995 and 2018. A remarkable double cyclone formed in 2012 and we present a detailed study of its dynamics using images from Mars Express and Mars Reconnaissance Orbiter obtained between 6 June and 9 July. A double cyclone was also observed in 2006 and 2008. In other Martian years the primary cyclone showed an annular cloud morphology with a large water ice cloud observed eastward of it. The cyclones have a size of ~600–800 km with a cloud‐free core of a radius ~100–300 km. Tangential velocities measured from cloud tracking in 2012 images are ~5–20 m/s−1at 10‐km altitude and double cyclone moved eastward with a velocity of 4 m/s−1during its lifetime of one month. The vortices grow in the morning hours, but with the increasing insolation as the sol progresses, a part of the clouds evaporate, the winds weaken, and the vortices lose coherence. This phenomenon forms under high‐temperature gradients in a region with a large north‐south topographic slope and has been recurrent each Martian year between 1995 and 2018. We argue the interest of studying its changing properties each Martian year in order to explore their possible relationship to the state of the Martian atmosphere at Ls~120°. We study a remarkable annular vortex observed some years to be formed by two coupled cyclones that grow every Martian northern summer at the same longitude and latitude of the planet. Each vortex has a size of 700 km and its center is a cloud‐free area with a radius of about 200 km. The vortex is formed by water ice clouds at about 10‐km altitude where the winds blow with speeds of 5 to 20 m/s. The clouds grow in the morning hours and sublimate as the vortex weakens with increasing insolation. Dynamical models show that the vortex forms in a region with a large north‐south terrain slope that combines with north‐south temperature gradient. The study mainly uses images taken in 2012, but a survey shows that the vortex recurrently forms every Martian year between 1995 and 2018. This vortex system can be used as a proxy, studying its variability, to characterize the state of the atmosphere at the time of its formation. We study the Mars seasonal annular cyclone and related phenomena at 60°N and 90°W at Ls= 120° from 1995 to 2018The cyclone is accompanied by a second structure, an annular vortex in 2006, 2008, and 2012, and an accompanying cloudy area other yearsWe show the wind field and cloud altitudes in 2012.Water ice clouds grow in the morning and weaken and dissipate as the sol advances

Recent measurements by the Imaging Ultraviolet Spectrograph (IUVS) instrument on NASA's Mars Atmosphere and Volatile EvolutioN mission show that a persistent layer of Mg+ions occurs around 90 km in the Martian atmosphere but that neutral Mg atoms are not detectable. These observations can be satisfactorily modeled with a global meteoric ablation rate of 0.06 t sol−1, out of a cosmic dust input of 2.7 ± 1.6 t sol−1. The absence of detectable Mg at 90 km requires that at least 50% of the ablating Mg atoms ionize through hyperthermal collisions with CO2molecules. Dissociative recombination of MgO+.(CO2)ncluster ions with electrons to produce MgCO3directly, rather than MgO, also avoids a buildup of Mg to detectable levels. The meteoric injection rate of Mg, Fe, and other metals—constrained by the IUVS measurements—enables the production rate of metal carbonate molecules (principally MgCO3and FeCO3) to be determined. These molecules have very large electric dipole moments (11.6 and 9.2 Debye, respectively) and thus form clusters with up to six H2O molecules at temperatures below 150 K. These clusters should then coagulate efficiently, building up metal carbonate‐rich ice particles which can act as nucleating particles for the formation of CO2‐ice clouds. Observable mesospheric clouds are predicted to occur between 65 and 80 km at temperatures below 95 K and above 85 km at temperatures about 5 K colder. When interplanetary dust particles enter a planetary atmosphere, collisions with air molecules cause heating and evaporation, a process termed meteoric ablation. This results in the continuous injection of metal atoms and ions into the planet's atmosphere. In the case of Earth, layers of metals such as Na and Fe have been observed for over 40 years. However, only very recently has a metallic layer been observed around another planet: a spectrometer on NASA's MAVEN spacecraft has detected a layer of Mg+ions around 95 km. The present study explores the unusual chemistry of metallic ions in a CO2atmosphere, and then develops a model of magnesium chemistry to explain the observed layer of Mg+and the surprising absence of a detectable Mg layer. The model predicts that metals like Mg and Fe form carbonates, which readily condense water to form “dirty” ice particles at the low temperatures of the Mars upper atmosphere. These particles provide the seeds on which CO2can condense at temperatures below −180°C, thus producing the clouds of CO2‐ice particles that have been observed by rovers on the surface of the planet and from orbiting spacecraft. A meteoric input function for Mars is generated by combining a cosmic dust input of ~3 tonnes sol−1with a chemical ablation modelMAVEN/IUVS observations of Mg+, and a small upper limit for Mg, suggest that around 50% of Mg atoms ionize directly after ablationMgCO3and FeCO3form stable H2O clusters which coagulate to metal‐rich ice particles, likely nuclei for clouds in the Martian mesosphere

We have developed new parameterizations of electrically neutral homogeneous and ion‐induced sulfuric acid‐water particle formation for large ranges of environmental conditions, based on an improved model that has been validated against a particle formation rate data set produced by Cosmics Leaving OUtdoor Droplets (CLOUD) experiments at European Organization for Nuclear Research (CERN). The model uses a thermodynamically consistent version of the Classical Nucleation Theory normalized using quantum chemical data. Unlike the earlier parameterizations for H2SO4‐H2O nucleation, the model is applicable to extreme dry conditions where the one‐component sulfuric acid limit is approached. Parameterizations are presented for the critical cluster sulfuric acid mole fraction, the critical cluster radius, the total number of molecules in the critical cluster, and the particle formation rate. If the critical cluster contains only one sulfuric acid molecule, a simple formula for kinetic particle formation can be used: this threshold has also been parameterized. The parameterization for electrically neutral particle formation is valid for the following ranges: temperatures 165–400 K, sulfuric acid concentrations 104–1013cm−3, and relative humidities 0.001–100%. The ion‐induced particle formation parameterization is valid for temperatures 195–400 K, sulfuric acid concentrations 104–1016cm−3, and relative humidities 10−5–100%. The new parameterizations are thus applicable for the full range of conditions in the Earth's atmosphere relevant for binary sulfuric acid‐water particle formation, including both tropospheric and stratospheric conditions. They are also suitable for describing particle formation in the atmosphere of Venus. Our H2SO4‐H2O parameterizations reproduce state‐of‐the‐art experimental and theoretical results for large ranges of environmental conditionsWe recommend replacing Vehkamäki et al. (2002, 2003) neutral particle formation parameterizations with ours and adding the ion‐induced pathwayCombination of neutral and ion‐induced pathways and the kinetic regime is required to describe H2SO4particle formation on Earth and Venus

Stellar occultation measurements conducted by the Mars Atmosphere and Volatile and EvolutioN/Imaging UltraViolet Spectrograph instrument were able to make vertically resolved measurements of ozone density in the middle atmosphere of Mars that offered good coverage with respect to latitude, longitude, and local time. These measurements were used to identify systematic variations in the vertical structure of ozone with longitude that could be distinguished from general trends in the evolution of ozone with respect to season and latitude. A total of 583 individual nightside occultations between Martian years 32 and 36 were analyzed, of which 224 were confirmed to have ozone, all found between Ls= 15°–165°. Close to aphelion (Ls= 60°–90°), peak ozone densities between 30 and 40 km altitude were observed to be within error of model predictions at all measured latitudes, but diverged from model predictions before and after this time. At low latitudes, seasonal changes were seen to have the greatest effect on the observed vertical structure of ozone, with detached ozone layer densities at altitudes above 30 km usually varying within approximately a factor of two along a given latitudinal band at a given time of year. Nonetheless, evidence of a persistent regional enhancement of ozone abundance was observed over equatorial latitudes during the aphelion season, spanning a longitude range of approximately 50°–130°E longitude. Planetary waves were clearly observed at higher Southern latitudes during Southern winter, often resulting in order of magnitude variations in ozone density with longitude. The presence of ozone is key to the stability of carbon dioxide in the Martian atmosphere, and can also be used to monitor Martian meteorology. Previous measurements of vertical variations of ozone in the Martian atmosphere relied on orbiters designed mostly to look for latitudinal and seasonal trends in ozone on Mars, with little information on how ozone varies with longitude. We used data from the Imaging UltraViolet Spectrograph instrument on board the Mars Atmosphere and Volatile and EvolutioN orbiter to make independent measurements of seasonal, latitudinal, longitudinal, and altitudinal variations of ozone in the Martian atmosphere from March 2015 to January 2022. Close to the Equator of Mars, ozone tended to vary more with season than with longitude. Nonetheless, we observed a region of increased ozone densities in the Eastern hemisphere of Mars, centered over the Equator. This region was consistently seen during the same season of each observed Martian year. At higher latitudes, variations with longitude tended to be much larger and more important than seasonal variations. Variations in ozone also exhibited wave structures at Southern subpolar latitudes, possibly indicating meteorological patterns in the middle atmosphere of Mars. The first study is presented distinguishing zonal variations in vertical ozone structure on Mars from seasonal and meridional trendsOzone variability is mostly driven by seasonal changes in the tropics but by zonal circulation patterns at higher latitudesPersistent regional enhancements in mesospheric ozone are observed at equatorial latitudes during aphelion season The first study is presented distinguishing zonal variations in vertical ozone structure on Mars from seasonal and meridional trends Ozone variability is mostly driven by seasonal changes in the tropics but by zonal circulation patterns at higher latitudes Persistent regional enhancements in mesospheric ozone are observed at equatorial latitudes during aphelion season

Peer review is the key to ensuring that the articles published in scientific journals such as JGR: Planetsare based on sound scientific principles, follow state‐of‐the‐art techniques, and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. JGR: Planetscovers an extraordinarily broad range of topics addressing every aspect of geoscience with the only requirement that the work addresses planetary processes. The breadth of topics published is reflected by our editorial team composed in 2022 of associate editors Jun Cui, Joel Davis, Leigh Fletcher, Matthias Grott, Ananya Mallik, German Martínez, Molly McCanta, Katarina Miljkovic, Ryan Park, Andrew Poppe, Beatrix Sánchez‐Cano, Mariek Schmidt, Yasuhito Sekine, Kelsi Singer, Sonia Tikoo, David Trang, and Zhiyong Xiao in addition to the editors who authored this note. We rely on the expertise of the community to vet the articles submitted to the journal. In 2022, JGR: Planetsbenefited from 1,299 reviews provided by 775 unique volunteer reviewers. We also received help from 29 guest editors working on seven active special collections. We know that all our volunteers juggle many duties, both professional and personal. We are forever grateful that they chose to dedicate their time and energy to evaluating submitted manuscripts and advising us on the suitability of each manuscript for our journal, often suggesting ways to improve the paper. Scientific publishing is truly a selfless community effort. The entire editorial board of JGR: Planetswishes to express their most heartfelt gratitude to the many scientists who chose to support their journal. Thank you! The expertise and dedication of peer reviewers are the keys to ensuring that the articles published in JGR: Planetsare thoroughly vetted and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. In 2022, JGR: Planetsbenefited from 1,299 reviews provided by 775 unique reviewers and from the help of 29 guest editors working on seven active special collections. We are forever grateful that so many scientists chose to dedicate their time and energy to evaluating and suggesting ways to improve each submitted manuscript. Scientific publishing is truly a community effort. The entire editorial board of JGR: Planetswishes to express here our most heartfelt gratitude to the many scientists who chose to support their journal. Thank you! Peer review ensures that JGR: Planetspublishes planetary science papers of the highest qualityIn 2022, 775 individuals provided 1,299 reviews of the submitted papersPeer reviewers: thank you for your service to the planetary community Peer review ensures that JGR: Planetspublishes planetary science papers of the highest quality In 2022, 775 individuals provided 1,299 reviews of the submitted papers Peer reviewers: thank you for your service to the planetary community

We report on daytime limb observations of Mars upper atmosphere acquired by the OMEGA instrument on board the European spacecraft Mars Express. The strong emission observed at 4.3 μm is interpreted as due to CO2fluorescence of solar radiation and is detected at a tangent altitude in between 60 and 110 km. The main value of OMEGA observations is that they provide simultaneously spectral information and good spatial sampling of the CO2emission. In this study we analyzed 98 dayside limb observations spanning over more than 3 Martian years, with a very good latitudinal and longitudinal coverage. Thanks to the precise altitude sounding capabilities of OMEGA, we extracted vertical profiles of the non‐local thermodynamic equilibrium (non‐LTE) emission at each wavelength and we studied their dependence on several geophysical parameters, such as the solar illumination and the tangent altitude. The dependence of the non‐LTE emission on solar zenith angle and altitude follows a similar behavior to that predicted by the non‐LTE model. According to our non‐LTE model, the tangent altitude of the peak of the CO2emission varies with the thermal structure, but the pressure level where the peak of the emission is found remains constant at ∼0.03 ± 0.01 Pa, . This non‐LTE model prediction has been corroborated by comparing SPICAM and OMEGA observations. We have shown that the seasonal variations of the altitude of constant pressure levels in SPICAM stellar occultation retrievals correlate well with the variations of the OMEGA peak emission altitudes, although the exact pressure level cannot be defined with the spectroscopy for the investigation of the characteristics of the atmosphere of Venus (SPICAM) nighttime data. Thus, observed changes in the altitude of the peak emission provide us information on the altitude of the 0.03 Pa pressure level. Since the pressure at a given altitude is dictated by the thermal structure below, the tangent altitude of the peak emission represents then an important piece of information of the atmosphere, of great value for validating general circulation models. We thus compared the altitude of OMEGA peak emission with the altitude of the 0.03 Pa level predicted by the Laboratoire de météorologie dynamique (LMD)‐Mars global circulation model and found that the peak emission altitudes from OMEGA present a much larger variability than the tangent altitude of the 0.03 Pa level predicted by the general circulation model. This variability could be possibly due to unresolved atmospheric waves. Further studies using this strong CO2limb emission data are proposed. We analyzed 3 Martian years of CO2fluorescence emission in Mars' upper atmosphereObservations are mainly affected by solar illumination conditions and the altitude of the emissionAccording to non‐LTE model, the peak of the emission occurs at a constant pressure level of 0.03 Pa

Inkjet printing technology has brought significant advances in patterning various functional materials that can meet important challenges in personalized medical treatments. Indeed, patterning of photothermal active anisotropic gold nanoparticles is particularly promising for the development of low-cost tools for localized photothermal therapy. In the present work, stable inks containing PEGylated gold nanostars (GNSs) were prepared and inkjet printed on a pigment-coated paper substrate. A significant photothermal effect (ΔT≅ 20 °C) of the printed patterns was observed under near infrared (NIR) excitation of the localized surface plasmon resonance (LSPR) of the GNS with low laser intensity (I≅ 0.2 W/cm2). Besides the pronounced photothermal effect, we also demonstrated, as an additional valuable effect, the release of a model fluorescent thiol-terminated Bodipy dye (BDP-SH) from the printed gold surface, both under bulk heating and NIR irradiation. These preliminary results suggest the way of the development of a new class of low-cost, disposable, and smart devices for localized thermal treatments combined with temperature-triggered drug release.

The Mars Orbiter Laser Altimeter (MOLA) instrument has been drawing a map of Mars' topography between September 1997 and June 2001. It has also been able to observe clouds during the mission duration, providing data for the low Martian atmosphere for nearly 1.5 Mars years. The Mars Global Surveyor, which carried MOLA, also carried two other instruments that also observed clouds during the same time period (the Mars Orbiter Camera and the Thermal Emission Spectrometer). Combining observations from these three data sets could provide a complete recap of most atmospheric structures during MY24 and MY25. However, previous studies of MOLA data set often had to use stringent detection criteria. Using machine learning clustering methods, we end up finding way more atmospheric returns. Our results are presented in the form of an atmospheric features catalog that we then use to compare MOLA observations with Mars Orbiter Camera and Thermal Emission Spectrometer results, but also with more recent missions. We study the development of recurrent phenomenon in the Martian atmosphere, like the aphelion cloud belt or the south polar hood, but also spontaneous events such as regional dust storms. Methods could be tuned even more finely by using more complex clustering methods or deep learning algorithms to clearly distinguish atmospheric structures. The Mars Orbiter Laser Altimeter (MOLA) instrument has been emitting laser pulses toward the Martian surface. Time of flight of the laser before returning to the instrument was originally used to estimate the altitude of Mars' surface, but the sensibility of the detector was good enough to detect clouds’ signatures coming from the atmosphere. We propose that studying the MOLA data set using machine learning methods that gather similar laser returns into groups can enable the formation of a cluster made of atmospheric features, distinguishing them from noise and surface returns. These features are then grouped into clouds or dust structures and compared with other mission results that also observed the Martian atmosphere between 1997 and 2001. This paints a picture of many phenomena in the low Martian atmosphere, their seasonal and interannual variability and their varying intensity. We reanalyze the Mars Orbiter Laser Altimeter data set with clustering methods and retrieve a new, large atmospheric structure data setComparing the data set with other observations allows us to provide a global view of atmospheric structuresWe observe the development of the aphelion cloud belt, the polar hoods, regional dust storms, and clouds over topographic features We reanalyze the Mars Orbiter Laser Altimeter data set with clustering methods and retrieve a new, large atmospheric structure data set Comparing the data set with other observations allows us to provide a global view of atmospheric structures We observe the development of the aphelion cloud belt, the polar hoods, regional dust storms, and clouds over topographic features

Background: Protected areas (PA) are central to biodiversity, but their efficiency is challenged by human-induced habitat loss and fragmentation. In the Fennoscandian boreal region, forestry with clearcutting is a threat to biodiversity causing the loss of mature forest elements and deterioration of ecological processes in forest landscapes, ultimately affecting PAs via declined structural connectivity. This paper aims to (1) determine PAs with high, red-listed species concentrations; (2) estimate the change in forest habitat around these PAs on different spatial scales; and (3) determine if forest management intensity is higher around biologically most valuable PAs. Occurrences of red-listed forest-dwelling species in Finland were used to identify PAs harbouring these species and to produce site-specific importance indices. CORINE landcover data was used as a baseline for the distribution of forests to assess the cover of clear-cuttings from 2001 to 2019 with the Global Forest Change (GFC) data set in three buffer areas around the PAs with occurrences of red-listed species. Results: The largest proportion of clear-cuts occurred in 1 km and 10 km buffers around the PAs in the southern and middle boreal zones, being ca. 20%. This indicates that the forest habitat is degrading fast at regional and landscape levels. On the positive side, the change in forest cover was lower around the biologically most important PAs compared to other PAs with red-listed species. Conclusions: Open and free satellite-data based assessments of the cover and change of forests provide reliable estimates about the rates at which mature and old-growth forests are being converted into young managed ones in Finland mainly via clear-cuts on different scales around PAs. The rate of clear-cuts was lowest in adjacent buffer areas next to the most species-rich PAs, which provides opportunities for biodiversity conservation efforts to be targeted to the remaining mature and old-growth forests found in the vicinity of these areas.

The aim of this work was to study the activity and functionality of laccase incorporated into laboratory-coated surface-sized paper. The effects of the physicochemical properties of the studied sized paper grades (permeability, porosity, and wetting) on the enzyme activity were studied. The enzymatic activity of laccase was measured either by following the oxidation of the substrate (mediator) with spectrophotometry or by monitoring the reduction of oxygen by luminescence quenching. The results showed that the initial activity of laccase incorporated into the coating did not decrease during the first 4 weeks and the activity was partly preserved even after 6 months. The functionality of the enzyme in sized papers was examined using 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) as the substrate. ABTS was inkjet-printed on the sized paper, and the reaction between laccase and ABTS appeared as a color change. The most important factor affecting the color response was the enzyme activity. Other beneficial factors affecting the color response were the hygroscopic nature and wettability of the sized paper. The results showed that the fabrication of bioactive paper is possible with a relatively simple strategy, i.e., by incorporation of the biomolecules in the coating formulation (paste). No major investments would be needed to start the production of this kind of environmentally sustainable, low-cost, and lightweight paper-based bio-indicator, e.g., for authentication applications.

The European Randomised study of Screening for Prostate Cancer (ERSPC) has shown significant reductions in prostate cancer mortality after 9 years and 11 years of follow-up, but screening is controversial because of adverse events such as overdiagnosis. We provide updated results of mortality from prostate cancer with follow-up to 2010, with analyses truncated at 9, 11, and 13 years.

Peer reviewing is the key to ensuring that the articles published in scientific journals such as JGR: Planetsare based on sound scientific principles, follow state‐of‐the‐art techniques, and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. Our journal covers an extraordinarily broad range of topics addressing every aspect of geoscience with the only requirement that the work should not be solely focused on the Earth. Our editorial team in 2021 comprised Gareth Collins, Jun Cui, Joel Davis, Caleb Fassett, Leigh Fletcher, Matthias Grott, Ananya Mallik, German Martínez, Molly McCanta, Ryan Park, Andrew Poppe, Beatrix Sanchez‐Cano, Mariek Schmidt, Yasuhito Sekine, Kelsi Singer, Sonia Tikoo, David Trang, and Zhiyong Xiao, in addition to the authors of this note. No matter how eclectic, our team cannot be specialized in every subject. With the universe as our playground, we rely on the expertise of the community to vet the articles submitted to the journal. In 2021, JGR: Planetsbenefited from 951 reviews provided by 597 unique reviewers. We also received help from 25 guest editors working on 5 active special collections. We know that most juggle many duties, both professional and personal. We are forever grateful that they chose to dedicate their time and energy to evaluating submitted manuscripts and advising us on the suitability of each manuscript for our journal, often suggesting ways to improve the paper. Scientific publishing truly is a community effort. The entire editorial board of JGR: Planetswishes to express here our most heartfelt gratitude to the many scientists who chose to support this journal, their journal. Thank you! The expertise and dedication of peer reviewers are the keys to ensuring that the articles published in JGR: Planetsare thoroughly vetted and present exciting discoveries or novel understanding of the fundamental processes that affect solar system objects. In 2021, JGR: Planetsbenefited from 951 reviews provided by 597 unique reviewers and from the help of 25 guest editors working on 5 active special collections. We are forever grateful that so many scientists chose to dedicate their time and energy to evaluating and suggesting ways to improve each submitted manuscript. Scientific publishing truly is a community effort. The entire editorial board of JGR: Planetswishes to express here our most heartfelt gratitude to the many scientists who chose to support this journal, their journal. Thank you! Peer review is crucial for the high‐quality planetary science published in JGR: PlanetsIn 2021, 597 individuals provided 951 reviews of submitted papersPeer reviewers: thank you for your service to the planetary community Peer review is crucial for the high‐quality planetary science published in JGR: Planets In 2021, 597 individuals provided 951 reviews of submitted papers Peer reviewers: thank you for your service to the planetary community

Prions are a novel form of infectivity based on the misfolding of a self-protein (PrPC) into a pathological, infectious isomer (PrPSc). The current uncontrolled spread of chronic wasting disease in cervids, coupled with the demonstrated zoonotic nature of select livestock prion diseases, highlights the urgent need for disease management tools. While there is proof-of-principle evidence for a prion vaccine, these efforts are complicated by the challenges and risks associated with induction of immune responses to a self-protein. Our priority is to develop a PrPSc-specific prion vaccine based on epitopes that are uniquely exposed upon misfolding. These disease specific epitopes (DSEs) have the potential to enable specific targeting of the pathological species through immunotherapy. Here we review outcomes of the translation of a prion DSE into a PrPSc-specific vaccine based on the criteria of immunogenicity, safety and specificity.

Species, as well as individuals within species, have unique susceptibilities to prion infection that are likely based on sequence differences in cellular prion protein (PrPC). Species barriers to transmission also reflect PrPCsequence differences. Defining the structure-activity relationship of PrPC/PrPScwith respect to infectivity/susceptibility will benefit disease understanding and assessment of transmission risks. Here, nanopore analysis is employed to investigate genotypes of sheep PrPCcorresponding to differential susceptibilities to scrapie infection. Under non-denaturing conditions scrapie resistant (ARR) and susceptible (VRQ) genotypes display similar, type I (bumping) predominant event profiles, suggesting a conserved folding pattern. Under increasingly denaturing conditions both proteins shift to type II (intercalation/translocation) events but with different sensitivities to unfolding. Specifically, when pre-incubated in 2M Gdn-HCl, the VRQ variant had more of type II events as compared with the ARR protein, suggesting a more flexible unfolding pattern. Addition of PrPSc-specific polyclonal antibody (YML) to the ARR variant, pre-incubated in 2M Gdn-HCl, reduced the number of type II events with no clear intercalation/translocation peak, whereas for VRQ, type II events above blockades of 90 pA bound YML. A second PrPSc-specific antibody (SN6b) to a different cryptic epitope reduced type II events for VRQ but not the ARR variant. Collectively, the event patterns associated with sequential denaturation, as well as interactions with PrPSc-specific antibodies, support unique patterns and/or propensities of misfolding between the genotypes. Overall, nanopore analysis identifies intermediate conformations that occur during the unfolding pathways of ARR and VRQ genotypes and may help to understand the correlation of structural properties that induce protein misfolding.

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative disorders caused by misfolding of a cellular protein PrPCinto an infectious conformation PrPSc. Previously our group demonstrated induction of PrPSc-specific antibodies with a SN6b vaccine that targets regions of the protein that are exposed upon misfolding. There are concerns that these antibodies could function as templates to promote misfolding and cause disease. To evaluate the consequences of prolonged exposure to PrPSc-specific antibodies in a prion sensitized animal, tga20 mice were vaccinated with the SN6b vaccine. No clinical signs of disease were detected up to 255 d post-vaccination, and postmortem assay of brains and spleens revealed no proteinase-K resistant PrP. These results suggest that vaccinating against TSEs with the SN6b antigen is safe from the standpoint of prion disease induction.

Transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases that are based on the misfolding of a cellular prion protein (PrPC) into an infectious, pathological conformation (PrPSc). There is proof-of-principle evidence that a prion vaccine is possible but this is tempered with concerns of the potential dangers associated with induction of immune responses to a widely-expressed self-protein. By targeting epitopes that are specifically exposed upon protein misfolding, our group developed a vaccine that induces PrPSc-specific antibody responses. Here we consider the ability of this polyclonal antibody (SN6b) to bind to a mutant of PrPCassociated with spontaneous prion disease. Polyclonal antibodies were selected to mimic the vaccination outcome and also explore all possible protein conformations of the recombinant bovine prion protein with mutation T194A [bPrP(T194A)]. This mutant is a homolog of the human T183A mutation of PrPCthat is associated with early onset of familial dementia. With nanopore analysis, under non-denaturing conditions, we observed binding of the SN6b antibody to bPrP(T194A). This interaction was confirmed through ELISAs as well as immunoprecipitation of the recombinant and cellularly expressed forms of bPrP(T194A). This interaction did not promote formation of a protease resistant conformation of PrP in vitro. Collectively, these findings support the disease-specific approach for immunotherapy of prion diseases but also suggest that the concept of conformation-specific immunotherapy may be complicated in individuals who are genetically predisposed to PrPCmisfolding.

ABSTRACTMycobacterium aviumsubsp. paratuberculosisis the causative agent of Johne's disease (JD) in cattle. M. aviumsubsp. paratuberculosisinfects the gastrointestinal tract of calves, localizing and persisting primarily in the distal ileum. A high percentage of cattle exposed to M. aviumsubsp. paratuberculosisdo not develop JD, but the mechanisms by which they resist infection are not understood. Here, we merge an established in vivobovine intestinal segment model for M. aviumsubsp. paratuberculosisinfection with bovine-specific peptide kinome arrays as a first step to understanding how infection influences host kinomic responses at the site of infection. Application of peptide arrays to in vivotissue samples represents a critical and ambitious step in using this technology to understand host-pathogen interactions. Kinome analysis was performed on intestinal samples from 4 ileal segments subdivided into 10 separate compartments (6 M. aviumsubsp. paratuberculosis-infected compartments and 4 intra-animal controls) using bovine-specific peptide arrays. Kinome data sets clustered into two groups, suggesting unique binary responses to M. aviumsubsp. paratuberculosis. Similarly, two M. aviumsubsp. paratuberculosis-specific immune responses, characterized by different antibody, T cell proliferation, and gamma interferon (IFN-?) responses, were also observed. Interestingly, the kinomic groupings segregated with the immune response groupings. Pathway and gene ontology analyses revealed that differences in innate immune and interleukin signaling and particular differences in the Wnt/ß-catenin pathway distinguished the kinomic groupings. Collectively, kinome analysis of tissue samples offers insight into the complex cellular responses induced by M. aviumsubsp. paratuberculosisin the ileum and provides a novel method to understand mechanisms that alter the balance between cell-mediated and antibody responses to M. aviumsubsp. paratuberculosisinfection.

The zebrafish (Danio rerio) is increasingly becoming an important model species for studies on the genetic and neural mechanisms controlling behaviour and cognition. Here, we utilized a conditioned place preference (CPP) paradigm to study social learning in zebrafish. We tested whether social interactions with conditioned demonstrators enhance the ability of focal naïve individuals to learn an associative foraging task. We found that the presence of conditioned demonstrators improved focal fish foraging behaviour through the process of social transmission, whereas the presence of inexperienced demonstrators interfered with the learning of the control focal fish. Our results indicate that zebrafish use social learning for finding food and that this CPP paradigm is an efficient assay to study social learning and memory in zebrafish.

Chaperones and foldases in the endoplasmic reticulum (ER) ensure correct protein folding. Extensive protein-protein interaction maps have defined the organization and function of many cellular complexes, but ER complexes are under-represented. Consequently, chaperone and foldase networks in the ER are largely uncharacterized. Using complementary ER-specific methods, we have mapped interactions between ER-lumenal chaperones and foldases and describe their organization in multiprotein complexes. We identify new functional chaperone modules, including interactions between protein-disulfide isomerases and peptidyl-prolyl cis-trans-isomerases. We have examined in detail a novel ERp72-cyclophilin B complex that enhances the rate of folding of immunoglobulin G. Deletion analysis and NMR reveal a conserved surface of cyclophilin B that interacts with polyacidic stretches of ERp72 and GRp94. Mutagenesis within this highly charged surface region abrogates interactions with its chaperone partners and reveals a new mechanism of ER protein-protein interaction. This ability of cyclophilin B to interact with different partners using the same molecular surface suggests that ER-chaperone/foldase partnerships may switch depending on the needs of different substrates, illustrating the flexibility of multichaperone complexes of the ER folding machinery.

Gold nanoparticles were synthesized and inkjet-printed on a paper substrate and IR-sintered to produce conductive electrodes. The electrodes were further functionalised by using self-assembled octadecanethiol monolayers (SAMs). The effect of sintering, print quality, and SAM formation were examined by topographical, chemical and electrical methods. With optimised printing parameters, a volume resistivity of ∼1.6 ×10–7Ω m was attained by a single print layer.

Background and Aims: Radiostereometric analysis (RSA) allows accurate three-dimensional measurements of micromotion in skeletal structures. The current RSA techniques are based on the analysis of scanned plain films. This study was undertaken to compare digital filmless RSA technique to conventional scanning technique using a phantom model of the ankle mortise.Material and Methods: In the first experiment, the relative displacement of the markers inserted to the fibula in relation to the markers inserted to the tibia was studied by means of double examinations and the precision of DICOM images were compared to scanned images of printed radiographs. In the second experiment, the film pair of double examination was re-imported or re-scanned and self-compared in order to show merely the error related to the image processing.Results: The precision of RSA using scanned images of printed radiographs was compatible to DICOM images. However, the mean error of rigid body fitting (ME) values were significantly lower in use of DICOM images compared with scanned radiographs, indicating less deformation of rigid body segments in filmless analysis.Conclusions: Precision of the RSA method was improved under the completely filmless environment. Therefore, this technique can be recommended for clinical studies of radiostereometric analysis.

Objective: Lead-time in prostate cancer screening was estimated using data from the Finnish randomized, population-based trial. Methods: Lead-time was defined as the duration of follow-up needed to accrue the same expected number of incident prostate cancer cases in the absence of screening as detected in the initial screening round. Expected numbers were calculated using an age-cohort model. Results: Based on findings among 10,000 men screened in 1996–1997 with 292 screen-detected cancers, lead-time was estimated as approximately 5–7 years, depending on the reference rates used. This corresponds to a mean duration of the detectable preclinical phase (DPCP) of 10–14 years, given that the cancers were detected on average at the midpoint of the DPCP. Conclusions: The findings suggest that a screening interval substantially longer than the 2 years generally used for mammography screening is unlikely to cause a substantial loss of sensitivity. A long screening interval is further justified in order to diminish the extent of overdiagnosis, until mortality effects can be evaluated.

Interpretation of musical works depends on meanings, which, on a pragmatist view, are necessarily tied with cultural habits and practices. This entails that a piece of music is always interpreted differently by people raised in different cultural contexts. A musical work is always a result of this process of interpretation. Strictly speaking, works of music are therefore different works in culturally different contexts even if they were presentations of the same notes. The following discussion of the conditions of cultural exchange in music illuminates some pragmatist viewpoints on the topic by using Keith Swanwick's ideas as a point of comparison. The discussion shows that a contextual starting point leads towards a more ‘child-centred’ education.

The interest toward flip chip technology has increased rapidly during last decade. Compared to the traditional packages and assembly technologies flip chip has several benefits, like less parasitics, the small package size and the weight. These properties emphasize especially when flip chip component is mounted direct to the flexible printed board. In this paper flip chip components with Kelvin four point probe and daisy chain test structure were bonded to the polyimide flex with two different types of anisotropically conductive adhesive films and one anisotropically conductive adhesive paste. The reliability of small pitch flip chip on flex interconnections (pitch 80 μm) was tested in 85°C/85% RH environmental test and −40↔+125°C thermal shock test. According to the results it is possible to achieve reliable and stable ohmic contact, even in small pitch flip chip on flex applications.

Performing biopsy in all men with a serum prostate specific antigen (PSA) of 3 to 3.9 ng./ml. increases the sensitivity of prostate cancer screening compared with a PSA cutoff of 4 ng./ml. but decreases specificity and may contribute to over diagnosis. Therefore, we evaluated the detection rate and specificity attributable to digital rectal examination and percent free PSA within the PSA range of 3 to 3.9 ng./ml.

It is not known whether screening of asymptomatic men with prostate specific antigen (PSA) decreases the mortality of prostate cancer. We evaluated the extent to which PSA screening identifies clinically significant prostate cancer by analyzing markers of biological aggressiveness.

Electrophysiological measurements have shown that contrast adaptation can increase the contrast gain of cortical cells of the cat and the monkey. This implies that adaptation could enhance the contrast discrimination sensitivity. Psychophysical contrast discrimination experiments were performed with and without contrast adaptation. The stimuli were spatially separated stationary Gabor patterns. The pedestal contrast was varied from 6 to 75 per cent. The spatial frequency was 1.5, 5.0 or 20 cpd. After adaptation the contrast detection thresholds are elevated and the subjective contrast is lowered. The contrast discrimination thresholds remain unchanged.

Analysis of data from a survey of employed adults in Detroit indicates that frequency of intoxication is associated with a masculine self-orientation among men and a feminine self-orientation among women during alcohol use. The study calls attention to the importance of fathers' drinking, life events, social class relations and a generalized alienation from self, work and society for understanding frequency of intoxication and masculine and feminine orientations during alcohol use. A path analysis suggests that the men and women who become intoxicated may regain a sense of self and relationships to others that they do not have in sober everyday life. Implications for future research on heavy drinking and self-orientations during alcohol use are discussed.

We have isolated the envZ gene from a recombinant plasmid carrying the complete ompB region of Salmonella typhimurium (Liljeström et al. 1982). The gene was found to be situated very near the ompR gene in the ompB locus. Using minicells, the envZ gene product was identified as a 46 kd protein. Strains harboring either an ompR+plasmid or an envZ+ompR+plasmid were found to differ in their response to environmental changes with respect to porin protein expression. The results obtained suggest that the EnvZ protein, together with ompR, ultimately determines the level of expression of the porin proteins.

Avascular necrosis of the nipple is a serious complication of reduction mammaplasty with nipple transposition. A study was undertaken to measure the skin circulation in the nipple before, during and after this operation. In 14 patients undergoing a reduction mammaplasty according to the method of Strömbeck, the skin circulation was measured in 25 breasts with laser doppler flowmetry (LDF) and fluorescein flowmetry (FF). LDF showed that the skin circulation increased after de-epithelialization to 204.4±31.0% of the preoperative value (100%) (mean ± SEM, p<0.01). After the upper and lower glandular resection the circulation was reduced to 90.7±12.3% of the preoperative value. The division of the lateral pedicle did not affect the circulation. After the skin had been sutured, the circulation was 71.5±9.1% of the preoperative value (p<0.01). One to four days postoperatively the circulation was 100.3±13.2% of the preoperative value. At FF uniform fluorescence was observed in the nipple postoperatively in all patients but two, in whom avascular necrosis later developed. Our results thus show that the circulation in the nipple after reduction mammaplasty by the Strömbeck method is adequate and that it is safe to divide the lateral dermal pedicle.

Intramuscular hemorrhage was induced by injecting autologous blood into the paraspinal muscle of 8 rabbits. In order to evaluate the time-dependent changes of hemorrhage observed on MRI, the animals were imaged at different stages of blood resolution at 0.02 tesla (T), and control examined with ultrasound using a 7.5 MHz linear transducer. Six inversion recovery sequences (TR= 1000 ms. TE = 30 ms, and TI = 18, 48, 148, 201, 302, and 398 ms) were used for the invivo calculation of T1 relaxation times. IR 1000 (398)/30 imaging was performed before and after the Gd-DOTA administration. The hemorrhage was evident on MR images throughout the study, especially on the T2 weighted (SE 1000/100) images. MRI showed the healing lesion longer than ultrasound. The T1 relaxation time increased during the time of resolution. Lesions on days 4 to 7 enhanced in intensity after the injection of Gd-DOTA.

Spin-lattice proton relaxation times (T1) in several biologic and phantom samples have been measured and analysed by using standard inversion recovery (IR) and spin echo (SE) sequences at 0.02 T. The average T1 of the sample was measured with the two-data point method. In the case of bi-exponential relaxation the value of a single T1 is strongly dependent on the T1 and TR selected. With short TI the T1 value obtained by using the two point method is approximately equal to the weighted average of the two relaxation time components (T1s and T1l), while at long inversion times TI the single T1 is more dependent on the long component T1l. The more the true short and long relaxation time components T1s and T1l of the bi-exponential relaxation differ from each other, the greater is the potential error, provided that the weights wsand wldo not differ very much. When two-data point analyzing method is used, the possible multi-exponential behaviour of the relaxation in tissues will be missed. For more reliable T1 values a series of images with as many values of TI as possible should be taken. Knowledge of true multi-exponential relaxation parameters helps in optimizing the sequence parameters and the image contrast between the various tissues.