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Clouds affect the Earth climate with an impact that depends on the cloud nature (solid and/or liquid water). Although the Antarctic climate is changing rapidly, cloud observations are sparse over Antarctica due to few ground stations and satellite observations. The Concordia station is located on the eastern Antarctic Plateau (75∘ S, 123∘ E; 3233 m above mean sea level), one of the driest and coldest places on Earth. We used observations of clouds, temperature, liquid water, and surface irradiance performed at Concordia during four austral summers (December 2018–2021) to analyse the link between liquid water and temperature and its impact on surface irradiance in the presence of supercooled liquid water (liquid water for temperature less than 0 ∘C) clouds (SLWCs). Our analysis shows that, within SLWCs, temperature logarithmically increases from −36.0 to −16.0 ∘C when liquid water path increases from 1.0 to 14.0 g m−2. The SLWC radiative forcing is positive and logarithmically increases from 0.0 to 70.0 W m−2 when liquid water path increases from 1.2 to 3.5 g m−2. This is mainly due to the downward longwave component that logarithmically increases from 0 to 90 W m−2 when liquid water path increases from 1.0 to 3.5 g m−2. The attenuation of shortwave incoming irradiance (that can reach more than 100 W m−2) is almost compensated for by the upward shortwave irradiance because of high values of surface albedo. Based on our study, we can extrapolate that, over the Antarctic continent, SLWCs have a maximum radiative forcing that is rather weak over the eastern Antarctic Plateau (0 to 7 W m−2) but 3 to 5 times larger over West Antarctica (0 to 40 W m−2), maximizing in summer and over the Antarctic Peninsula.

Soil erosion by water, and the consequent loss of a non-renewable resource, is a relevant environmental issue which has economic, ecologic, and social repercussions. In the context of the European Green Deal, the increasing awareness of soil Ecosystem Services is leading to give the due relevance to this problem. Notwithstanding the recent soil conservation strategies adopted by the Common Agricultural Policy had positive effects, the concern regarding this topic is drastically increasing for the normalization of extraordinary rainfall events due to climate change. Recent events occurred in Europe demonstrated that landscape protection is often inadequate and interventions to prevent damages due to hydrogeological instability are scarce.The determination of a “tolerable” soil loss TSL is useful to establish a quantitative standard to measure the effectiveness of strategies and techniques to control soil erosion. However, soil conservation strategies/works designed by the mean annual value of the climatic variable, as the rainfall erosivity factor R, are not appropriate for some erosive events which produce intolerable sediment yield values. Therefore, the adoption of an adequate TSL, which could help to ensure the protection of soil functions and a sustainable soil use, should be a primary goal to reach for policy makers.In this paper, a new method to define the tolerable soil loss is proposed. This approach is based on the statistical analysis of the measured annual values of R and leads to the determination of the cover and management factor for which the maximum tolerable soil loss is equal to the annual soil loss of given return period. The analysis demonstrated that to limit soil erosion to the tolerable soil loss, interventions to change land use, reduce field length or apply support practices can be carried out.

The organic mass fraction from sea spray aerosol (SSA) is currently a subject of intense research. The majority of this research is dedicated to measurements in ambient air. However a number of studies have recently started to focus on nascent sea spray aerosol. This work presents measurements collected during a 5-week cruise in May and June 2017 in the central and western Mediterranean Sea, an oligotrophic marine region with low phytoplankton biomass. Surface seawater was continuously pumped into a bubble-bursting apparatus to generate nascent sea spray aerosol. Size distributions were measured with a differential mobility particle sizer (DMPS). Chemical characterization of the submicron aerosol was performed with a time-of-flight aerosol chemical speciation monitor (ToF-ACSM) operating with 10 min time resolution and with filter-based chemical analysis on a daily basis. Using positive matrix factorization analysis, the ToF-ACSM non-refractory organic matter (OMNR) was separated into four different organic aerosol types, identified as primary OA (POANR), oxidized OA (OOANR), methanesulfonic acid type OA (MSA-OANR), and mixed OA (MOANR). In parallel, surface seawater biogeochemical properties were monitored providing information on phytoplankton cell abundance and seawater particulate organic carbon (1 h time resolution) and seawater surface microlayer (SML) dissolved organic carbon (DOC) (on a daily basis). Statistically robust correlations (for n>500) were found between MOANR and nanophytoplankton cell abundance, as well as between POANR, OOANR, and particulate organic carbon (POC). Parameterizations of the contributions of different types of organics to the submicron nascent sea spray aerosol are proposed as a function of the seawater biogeochemical properties for use in models.

Ice-nucleating particles (INPs) have a large impact on the climate-relevant properties of clouds over the oceans. Studies have shown that sea spray aerosols (SSAs), produced upon bursting of bubbles at the ocean surface, can be an important source of marine INPs, particularly during periods of enhanced biological productivity. Recent mesocosm experiments using natural seawater spiked with nutrients have revealed that marine INPs are derived from two separate classes of organic matter in SSAs. Despite this finding, existing parameterizations for marine INP abundance are based solely on single variables such as SSA organic carbon (OC) or SSA surface area, which may mask specific trends in the separate classes of INP. The goal of this paper is to improve the understanding of the connection between ocean biology and marine INP abundance by reporting results from a field study and proposing a new parameterization of marine INPs that accounts for the two associated classes of organic matter. The PEACETIME cruise took place from 10 May to 10 June 2017 in the Mediterranean Sea. Throughout the cruise, INP concentrations in the surface microlayer (INPSML) and in SSAs (INPSSA) produced using a plunging aquarium apparatus were continuously monitored while surface seawater (SSW) and SML biological properties were measured in parallel. The organic content of artificially generated SSAs was also evaluated. INPSML concentrations were found to be lower than those reported in the literature, presumably due to the oligotrophic nature of the Mediterranean Sea. A dust wet deposition event that occurred during the cruise increased the INP concentrations measured in the SML by an order of magnitude, in line with increases in iron in the SML and bacterial abundances. Increases in INPSSA were not observed until after a delay of 3 days compared to increases in the SML and are likely a result of a strong influence of bulk SSW INPs for the temperatures investigated (T=-18 ∘C for SSAs, T=-15 ∘C for SSW). Results confirmed that INPSSA are divided into two classes depending on their associated organic matter. Here we find that warm (T≥-22 ∘C) INPSSA concentrations are correlated with water-soluble organic matter (WSOC) in the SSAs, but also with SSW parameters (particulate organic carbon, POCSSW and INPSSW,-16C) while cold INPSSA (T<-22 ∘C) are correlated with SSA water-insoluble organic carbon (WIOC) and SML dissolved organic carbon (DOC) concentrations. A relationship was also found between cold INPSSA and SSW nano- and microphytoplankton cell abundances, indicating that these species might be a source of water-insoluble organic matter with surfactant properties and specific IN activities. Guided by these results, we formulated and tested multiple parameterizations for the abundance of INPs in marine SSAs, including a single-component model based on POCSSW and a two-component model based on SSA WIOC and OC. We also altered a previous model based on OCSSA content to account for oligotrophy of the Mediterranean Sea. We then compared this formulation with the previous models. This new parameterization should improve attempts to incorporate marine INP emissions into numerical models.

We present the laboratory results of immersion freezing efficiencies of cellulose particles at supercooled temperature (T) conditions. Three types of chemically homogeneous cellulose samples are used as surrogates that represent supermicron and submicron ice-nucleating plant structural polymers. These samples include microcrystalline cellulose (MCC), fibrous cellulose (FC) and nanocrystalline cellulose (NCC). Our immersion freezing dataset includes data from various ice nucleation measurement techniques available at 17 different institutions, including nine dry dispersion and 11 aqueous suspension techniques. With a total of 20 methods, we performed systematic accuracy and precision analysis of measurements from all 20 measurement techniques by evaluating T-binned (1 ∘C) data over a wide T range (−36 ∘C 

BACKGROUND: Preventing Loss of Independence through Exercise (PLIÉ) is a group program for people living with dementia that combines movements to support daily function with present moment body awareness and social engagement that has been found to have physical, emotional, social, and cognitive benefits. The goal of this study was to develop and refine a PLIÉ remote training program for interdisciplinary Veterans Affairs (VA) nursing home staff members also known as community living center (CLC) staff. METHODS: This pre-implementation study used iterative Plan-Do-Study-Act (PDSA) cycles. The 10-week PDSA cycles occurred from June to September 2021 at 2 VA nursing home sites. Remote training was delivered via Microsoft Teams and included 1-hour live-streamed weekly didactic sessions (nursing staff with PLIÉ instructor) focused on PLIÉ principles and 1-hour weekly live-streamed experiential sessions for staff to apply PLIÉ principles with residents. We administered weekly feedback surveys to iteratively refine the training process. RESULTS: 14 staff members participated (5 recreation therapists, 3 social workers, 2 registered nurses, 2 chaplains, 1 psychologist, and 1 speech pathologist). The experiential sessions were rated as most helpful overall. Key PDSA refinements included: (1) creating 10-minute video recording summaries to support learning, particularly for those unable to attend live training sessions due to clinical schedules; and (2) incorporating self-reflection and goal setting to support staff incorporation of PLIÉ principles into routine care and personal life. These refinements resulted in increased use of PLIÉ principles with the residents from 67 to 89% of the staff participants. 100% of regular attendees (11/11) rated their overall satisfaction with remote training as very good or excellent. CONCLUSIONS: It was feasible to train interdisciplinary CLC staff participants to deliver an integrative group movement program for residents with dementia remotely. PDSA cycles supported refinement of the training process and improved uptake. A larger study of PLIÉ remote CLC staff training is needed to assess outcomes on residents and quality of care.

The second phase of the Fifth International Ice Nucleation Workshop (FIN-02) involved the gathering of a large number of researchers at the Karlsruhe Institute of Technology's Aerosol Interactions and Dynamics of the Atmosphere (AIDA) facility to promote characterization and understanding of ice nucleation measurements made by a variety of methods used worldwide. Compared to the previous workshop in 2007, participation was doubled, reflecting a vibrant research area. Experimental methods involved sampling of aerosol particles by direct processing ice nucleation measuring systems from the same volume of air in separate experiments using different ice nucleating particle (INP) types, and collections of aerosol particle samples onto filters or into liquid for sharing amongst measurement techniques that post-process these samples. In this manner, any errors introduced by differences in generation methods when samples are shared across laboratories were mitigated. Furthermore, as much as possible, aerosol particle size distribution was controlled so that the size limitations of different methods were minimized. The results presented here use data from the workshop to assess the comparability of immersion freezing measurement methods activating INPs in bulk suspensions, methods that activate INPs in condensation and/or immersion freezing modes as single particles on a substrate, continuous flow diffusion chambers (CFDCs) directly sampling and processing particles well above water saturation to maximize immersion and subsequent freezing of aerosol particles, and expansion cloud chamber simulations in which liquid cloud droplets were first activated on aerosol particles prior to freezing. The AIDA expansion chamber measurements are expected to be the closest representation to INP activation in atmospheric cloud parcels in these comparisons, due to exposing particles freely to adiabatic cooling.The different particle types used as INPs included the minerals illite NX and potassium feldspar (K-feldspar), two natural soil dusts representative of arable sandy loam (Argentina) and highly erodible sandy dryland (Tunisia) soils, respectively, and a bacterial INP (Snomax®). Considered together, the agreement among post-processed immersion freezing measurements of the numbers and fractions of particles active at different temperatures following bulk collection of particles into liquid was excellent, with possible temperature uncertainties inferred to be a key factor in determining INP uncertainties. Collection onto filters for rinsing versus directly into liquid in impingers made little difference. For methods that activated collected single particles on a substrate at a controlled humidity at or above water saturation, agreement with immersion freezing methods was good in most cases, but was biased low in a few others for reasons that have not been resolved, but could relate to water vapor competition effects. Amongst CFDC-style instruments, various factors requiring (variable) higher supersaturations to achieve equivalent immersion freezing activation dominate the uncertainty between these measurements, and for comparison with bulk immersion freezing methods. When operated above water saturation to include assessment of immersion freezing, CFDC measurements often measured at or above the upper bound of immersion freezing device measurements, but often underestimated INP concentration in comparison to an immersion freezing method that first activates all particles into liquid droplets prior to cooling (the PIMCA-PINC device, or Portable Immersion Mode Cooling chAmber–Portable Ice Nucleation Chamber), and typically slightly underestimated INP number concentrations in comparison to cloud parcel expansions in the AIDA chamber; this can be largely mitigated when it is possible to raise the relative humidity to sufficiently high values in the CFDCs, although this is not always possible operationally.Correspondence of measurements of INPs among direct sampling and post-processing systems varied depending on the INP type. Agreement was best for Snomax® particles in the temperature regime colder than −10 °C, where their ice nucleation activity is nearly maximized and changes very little with temperature. At temperatures warmer than −10 °C, Snomax® INP measurements (all via freezing of suspensions) demonstrated discrepancies consistent with previous reports of the instability of its protein aggregates that appear to make it less suitable as a calibration INP at these temperatures. For Argentinian soil dust particles, there was excellent agreement across all measurement methods; measures ranged within 1 order of magnitude for INP number concentrations, active fractions and calculated active site densities over a 25 to 30 °C range and 5 to 8 orders of corresponding magnitude change in number concentrations. This was also the case for all temperatures warmer than −25 °C in Tunisian dust experiments. In contrast, discrepancies in measurements of INP concentrations or active site densities that exceeded 2 orders of magnitude across a broad range of temperature measurements found at temperatures warmer than −25 °C in a previous study were replicated for illite NX. Discrepancies also exceeded 2 orders of magnitude at temperatures of −20 to −25 °C for potassium feldspar (K-feldspar), but these coincided with the range of temperatures at which INP concentrations increase rapidly at approximately an order of magnitude per 2 °C cooling for K-feldspar.These few discrepancies did not outweigh the overall positive outcomes of the workshop activity, nor the future utility of this data set or future similar efforts for resolving remaining measurement issues. Measurements of the same materials were repeatable over the time of the workshop and demonstrated strong consistency with prior studies, as reflected by agreement of data broadly with parameterizations of different specific or general (e.g., soil dust) aerosol types. The divergent measurements of the INP activity of illite NX by direct versus post-processing methods were not repeated for other particle types, and the Snomax® data demonstrated that, at least for a biological INP type, there is no expected measurement bias between bulk collection and direct immediately processed freezing methods to as warm as −10 °C. Since particle size ranges were limited for this workshop, it can be expected that for atmospheric populations of INPs, measurement discrepancies will appear due to the different capabilities of methods for sampling the full aerosol size distribution, or due to limitations on achieving sufficient water supersaturations to fully capture immersion freezing in direct processing instruments. Overall, this workshop presents an improved picture of present capabilities for measuring INPs than in past workshops, and provides direction toward addressing remaining measurement issues.

BACKGROUND: The COVID-19 pandemic and shut down of in-person complementary and integrative (CIH) wellness services at the San Francisco Veterans Affairs Healthcare System (SFVAHCS) required implementation of virtual program delivery. In May 2020, VA in-person group yoga classes pivoted to virtual classes for existing attendees. In October 2020, we partnered with SFVAHCS Integrative Health and the VA Office of Rural Health to formalize the TeleYoga Program to expand yoga access to Veterans in SFVAHCS geographically dispersed area. OBJECTIVE: This pilot study evaluated Veterans experiences and self-reported health outcomes after participating in at-home tele-yoga groups during the COVID-19 pandemic. METHODS: The RE-AIM framework guided program delivery evaluation. Reach was assessed with medical record data. Adoption was assessed by the number of new facilities providing referrals to tele-yoga. Implementation, satisfaction, and patient-reported outcomes, were evaluated through structured interviews with Likert scale and open-ended responses. RESULTS: We offered 4-6 weekly livestreamed classes between October 2020-September 2021. The program reached 70 Veterans, including 40 new participants, with 1208 total unique encounters. Referrals increased from 2 to 6 SFVAHCS facilities. Fourteen participants completed structured interviews. Over half rated highly the convenience and overall experience of tele-yoga classes and reported improvement with pain, stress management, exercise, and flexibility. Open-ended responses indicated opportunities for social connection, maintaining mental health, cultivating resilience, improving function, and managing pain. Suggestions for improvement focused on technological aspects, including audiovisual quality. CONCLUSIONS: During the COVID-19 pandemic, we successfully transitioned and expanded virtual group yoga delivery to Veterans from all geographic locations within SFVAHCS. We attribute this success to existing infrastructure for telehealth and CIH services and a virtual program orientation for new participants. The results of this pilot study suggest in-person group yoga may be successfully implemented virtually, serving as a viable modality that contributes to holistic wellbeing for Veterans.

INTRODUCTION: There are few widely-available, evidence-based options to support quality of life (QOL) for people living with Alzheimers disease and related dementias. METHODS: We performed a randomized, controlled trial with a Waitlist control group to determine whether an online, livestream, mind-body, group movement program (Moving Together, 1 hour, 2 days/week, 12 weeks) improves QOL in people with cognitive impairment (PWCI) or care partners (CPs) and explore mechanisms of action. The primary outcome for both participants was self-reported QOL. Secondary outcomes and potential mediators included mobility, isolation, well-being, cognitive function, and sleep in PWCI and burden, positive emotions, caregiver self-efficacy, stress management, and sleep in CPs. Blinded assessors collected outcome data at baseline, 12, and 24 weeks. We assessed adverse events including falls through monthly check-in surveys and collected qualitative data through evaluation surveys. Intention-to-treat analyses used linear mixed models to compare mean change over time between groups and calculated standardized effect sizes (ESs). RESULTS: Ninety-seven dyads enrolled (PWCI: age 76 ± 11 years, 43% female, 80% non-Hispanic White; CPs: age 66 ± 12 years, 78% female, 71% non-Hispanic White); 15% withdrew before 12 weeks and 22% before 24 weeks. PWCI self-reported significantly better QOL from baseline to 12 weeks in the Moving Together group compared to the Waitlist group (ES = 0.474, p = 0.048) and CPs self-reported improved ability to manage stress (ES = 0.484, p = 0.021). Improvements in participant self-reported QOL were mediated by improvements in their self-reported well-being and CP-reported ability to manage stress. Results were similar when the Waitlist group participated in the program (QOL ES = 0.663, p = 0.006; stress management ES = 0.742, p = 0.002) and were supported by qualitative data. Exploratory analyses suggested possible fall reduction in PWCI. There were no study-related serious adverse events. DISCUSSION: Online programs such as Moving Together offer a scalable strategy for supporting high QOL for PWCI and helping CPs manage stress. TRIAL REGISTRATION: ClinicalTrials.gov NCT04621448. HIGHLIGHTS: The approval of new medications that slow cognitive decline in people living with Alzheimers disease and related disorders (ADRD) has raised hope and excitement. However, these medications do not appear to impact quality of life, which is often considered by patients and care partners to be the most important outcome.In this randomized clinical trial, we found that an evidence-based, online, livestream, mind-body, group movement program significantly and meaningfully improves self-rated quality of life in people with ADRD and helps care partners manage stress. Mediation analyses revealed that the key drivers of improvements in participants quality of life were improvements in their feelings of well-being and care partners ability to manage stress. Exploratory analyses also suggested a 30% reduction in falls.These results are important because they suggest that an online program, which is available now and can be performed by people from the comfort of home or other location of choice, could be recommended as a complement or alternative to new therapies to help maximize quality of life for people living with ADRD and their care partners.

Mind-wandering (MW) is a universal cognitive process that is estimated to comprise [approximately] 30% of our everyday thoughts. Despite its prevalence, the functional utility of MW remains a scientific blind spot. The present study sought to investigate whether MW serves a functional role in cognition. Specifically, we investigated whether MW contributes to memory consolidation-like processes, and if age differences in the ability to reactivate episodic memories during MW may contribute to age-related declines in episodic memory. Younger and older adults encoded paired associates, received targeted reactivation cues during an interval filled with a task that promotes MW, and were tested on their memory for the cued and uncued stimuli from the initial encoding task. Thought probes were presented during the retention (MW) interval to assess participants' thought contents. Across four experiments, we compared the effect of different cue modalities (i.e., auditory, visual) on cued recall performance, and examined both correct retrieval RTs as well as accuracy. Across experiments, there was evidence that stimuli that were cued during the MW task were correctly retrieved more quickly than uncued stimuli and that this effect was more robust for younger adults than older adults. Additionally, the more MW a participant reported during the retention interval, the stronger the cuing effect they produced during retrieval. The results from these experiments are interpreted within a retrieval facilitation framework wherein cues serve to reactivate the earlier traces during MW, and this reactivation benefits retrieval speed for cued items compared with uncued items.

Sediments collected from hypersaline and anoxic deep-sea basins in the eastern Mediterranean (Thetis, Kryos, Medee, and Tyro) were characterised in terms of their mineralogical composition, the distributions of rare earth elements (REE), Zr, and Hf and their content of microbial DNA. We identified two major mineralogical fractions: one fraction of detritic origin was composed of quartz, gypsum, and low-Mg calcite bioclasts (with 0 < Mg < 0.07%) and another fraction of authigenic origin constituted of halite, dolomite, high-Mg calcite (with a Mg content of up to 22%) and rare bischofite and showed a textural evidence of microbial assemblages. We found that in the Medee and Tyro sediments, the shale-normalised REE pattern of these sediments is strongly enriched in middle REE (MREE), whereas in the Thetis and Tyro basins, a positive Gd anomaly in the residue was obtained after the removal of the water-soluble fraction. In all investigated basins, Y / Ho ratio clustered around chondritic values, whereas Zr / Hf ratio ranged from slightly subchondritic to superchondritic values. Subchondritic Y / Ho and Zr / Hf values were mainly found in the high-Mg carbonate having a microbial origin. The observed preferential removal of Zr with respect to Hf without significant partitioning of Y with respect to Ho indicates that the Zr / Hf ratio and Y–Ho fractionations are influenced by the microbial activity in the sediments. We propose that the concurrent Y-Ho and Zr–Hf fractionations are a suitable tracer of microbial activity in marine sediments.

Sex differences in glioblastoma (GBM) incidence and outcome are well recognized, and emerging evidence suggests that these extend to genetic/epigenetic and cellular differences, including immune responses. However, the mechanisms driving immunologic sex differences are not fully understood. Here, we demonstrate that T cells play a critical role in driving GBM sex differences. Male mice exhibited accelerated tumor growth, with decreased frequency and increased exhaustion of CD8+ T cells in the tumor. Furthermore, a higher frequency of progenitor exhausted T cells was found in males, with improved responsiveness to anti-PD-1 treatment. Moreover, increased T-cell exhaustion was observed in male GBM patients. Bone marrow chimera and adoptive transfer models indicated that T cell-mediated tumor control was predominantly regulated in a cell-intrinsic manner, partially mediated by the X chromosome inactivation escape gene Kdm6a. These findings demonstrate that sex-biased predetermined behavior of T cells is critical for inducing sex differences in GBM progression and immunotherapy response.SignificanceImmunotherapies in patients with GBM have been unsuccessful due to a variety of factors, including the highly immunosuppressive tumor microenvironment in GBM. This study demonstrates that sex-biased T-cell behaviors are predominantly intrinsically regulated, further suggesting sex-specific approaches can be leveraged to potentially improve the therapeutic efficacy of immunotherapy in GBM. See related commentary by Alspach, p. 1966. This article is featured in Selected Articles from This Issue, p. 1949.