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We present an Arctic aerosol optical depth (AOD) climatology and trend analysis for 2003–2019 spring and summertime periods derived from a combination of multi-agency aerosol reanalyses, remote-sensing retrievals, and ground observations. This includes the U.S. Navy Aerosol Analysis and Prediction System ReAnalysis version 1 (NAAPS-RA v1), the NASA Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), and the Copernicus Atmosphere Monitoring Service ReAnalysis (CAMSRA). Spaceborne remote-sensing retrievals of AOD are considered from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Multi-angle Imaging SpectroRadiometer (MISR), and the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). Ground-based data include sun photometer data from AErosol RObotic NETwork (AERONET) sites and oceanic Maritime Aerosol Network (MAN) measurements. Aerosol reanalysis AODs and spaceborne retrievals show consistent climatological spatial patterns and trends for both spring and summer seasons over the lower Arctic (60–70∘ N). Consistent AOD trends are also found for the high Arctic (north of 70∘ N) from reanalyses. The aerosol reanalyses yield more consistent AOD results than climate models, can be verified well with AERONET, and corroborate complementary climatological and trend analysis. Speciated AODs are more variable than total AOD among the three reanalyses and a little more so for March–May (MAM) than for June–August (JJA). Black carbon (BC) AOD in the Arctic comes predominantly from biomass burning (BB) sources in both MAM and JJA, and BB overwhelms anthropogenic sources in JJA for the study period. AOD exhibits a multi-year negative MAM trend and a positive JJA trend in the Arctic during 2003–2019, due to an overall decrease in sulfate/anthropogenic pollution and a significant JJA increase in BB smoke. Interannual Arctic AOD variability is significantly large, driven by fine-mode and, specifically, BB smoke, with both smoke contribution and interannual variation larger in JJA than in MAM. It is recommended that climate models should account for BB emissions and BB interannual variabilities and trends in Arctic climate change studies.

Diarrhea is a major cause of illness and death in preweaned calves and causes significant economic losses to producers. A better understanding of the fecal microbiota in diarrheic and nondiarrheic calves could lead to improved treatment and prevention strategies. The purpose of this study was to compare the fecal microbiota of diarrheic and nondiarrheic calves to improve our understanding of what constitutes a healthy fecal microbiota in preweaned calves. At each of 7 farms, fecal samples were obtained from 1 to 3 diarrheic Holstein dairy calves (2 to 17 d old at sampling time) and age-matched (within 5 d) nondiarrheic controls for a total of 20 samples. Calves were fed either acidified bulk milk, pasteurized or unpasteurized waste milk, or milk replacer depending on farm. Fecal samples were extracted for genomic DNA, PCR-amplified for the V1-V2 region of the 16S rRNA bacterial gene, sequenced on the Illumina MiSeq (Illumina Inc., San Diego, CA) platform, and analyzed using QIIME2. Firmicutes and Bacteroidetes were the most abundant phyla in both groups; Fusobacteria was numerically more abundant in the diarrheic group, whereas Proteobacteria and Actinobacteria were numerically more abundant in the nondiarrheic group. At the genus level, Bacteroides was the most abundant genus in both groups and was numerically more abundant in the nondiarrheic group. Results from the mixed-effects regression model showed that Faecalibacterium and Butyricimonas were more abundant in the nondiarrheic calves, whereas Clostridium and Peptostreptococcus were more abundant in the diarrheic calves. Our results indicate that commensal bacteria acquired in the neonatal period may have been replaced with potential pathogens in diarrheic calves, which may have contributed to the incidence of diarrhea either directly or indirectly.

Numerical weather prediction systems depend on Hyperspectral Infrared Sounder (HIS) data, yet the impacts of dust-contaminated HIS radiances on weather forecasts has not been quantified. To determine the impact of dust aerosol on HIS radiance assimilation, we use a modified radiance assimilation system employing a one-dimensional variational assimilation system (1DVAR) developed under the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Numerical Weather Prediction–Satellite Application Facility (NWP-SAF) project, which uses the Radiative Transfer for TOVS (RTTOV). Dust aerosol impacts on analyzed temperature and moisture fields are quantified using synthetic HIS observations from rawinsonde, Micropulse Lidar Network (MPLNET), and Aerosol Robotic Network (AERONET). Specifically, a unit dust aerosol optical depth (AOD) contamination at 550 nm can introduce larger than 2.4 and 8.6 K peak biases in analyzed temperature and dewpoint, respectively, over our test domain. We hypothesize that aerosol observations, or even possibly forecasts from aerosol predication models, may be used operationally to mitigate dust induced temperature and moisture analysis biases through forward radiative transfer modeling.

Modern agri-food systems generate large amounts of crop-based biomass that are unfit for direct human consumption but potentially eligible for upcycling via livestock feeding for production of meats, milk, and eggs. This study aims to develop novel feeds for cattle from some of those biomass materials through the natural microbial-driven processes of ensiling. Fruit and vegetables resembling supermarket discards were ensiled alone or co-ensiled with corn crop residues, mushroom wastes, etc. via laboratory experiments. Longitudinal sample analyses showed that (co-)ensiling was successful, with pH and fermentation acids falling within desirable ranges (pH in vitro incubation results indicated that the ensiled products could substitute certain conventional feeds while maintaining diet digestibility. Our findings provide a proof of principle for generating quality novel feeds for cattle from food discards and under-utilized crop residues. Future scale-up studies and animal feeding trials to demonstrate the utility of this approach can help societies begin re-purposing and more effectively utilizing otherwise-untapped feedstock resources, strengthening the regenerative capacity of agri-food systems towards a more sustainable food future.

Modern agri-food systems generate large amounts of crop-based biomass that are unfit for direct human consumption but potentially suitable for livestock feeding in production of meats, milk, and eggs. This study aims to develop novel feeds for cattle from some of those biomass materials through the natural microbial-driven processes of ensiling. Fruit and vegetables resembling supermarket discards were ensiled alone or co-ensiled with corn crop residues, mushroom wastes, etc. via laboratory experiments. Longitudinal sample analyses showed that (co-)ensiling was successful, with pH and fermentation acids changing rapidly into desirable ranges (pH

Background MAT9001 is an omega‐3 free fatty acid (FFA) formulation containing mainly eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA). Compared with icosapent ethyl (EPA‐ethyl esters [EE]), EPA+DPA‐FFA previously showed enhanced triglyceride lowering and higher plasma EPA when both were administered once daily with a very–low fat diet. This trial compared pharmacodynamic responses and plasma omega‐3 levels following twice daily dosing, with meals, of EPA+DPA‐FFA and EPA‐EE in hypertriglyceridemic subjects consuming a Therapeutic Lifestyle Changes diet. Methods and Results This open‐label, randomized, 2‐way crossover trial, with 28‐day treatment periods separated by ≥28‐day washout, was conducted at 8 US centers and included 100 subjects with fasting triglycerides 1.70 to 5.64 mmol/L (150–499 mg/dL) (median 2.31 mmol/L [204 mg/dL]; 57% women, average age 60.3 years). The primary end point was least squares geometric mean percent change from baseline plasma triglycerides. In the 94 subjects with analyzable data for both treatment periods, EPA+DPA‐FFA and EPA‐EE reduced least squares geometric mean triglycerides from baseline: 20.9% and 18.3%, respectively ( P =not significant). EPA+DPA‐FFA reduced least squares geometric mean high‐sensitivity C‐reactive protein by 5.8%; EPA‐EE increased high‐sensitivity C‐reactive protein by 8.5% ( P =0.034). EPA+DPA‐FFA increased least squares geometric mean plasma EPA, DPA, and total omega‐3 (EPA+docosahexaenoic acid+DPA) concentrations by 848%, 177%, and 205%, respectively, compared with corresponding changes with EPA‐EE of 692%, 140%, and 165% (all P P =0.011). Lipoprotein cholesterol and apolipoprotein responses did not differ between treatments. Conclusions EPA+DPA‐FFA raised plasma EPA, DPA, and total omega‐3 significantly more than did EPA‐EE. EPA+DPA‐FFA also reduced triglycerides and high‐sensitivity C‐reactive protein without increasing low‐density lipoprotein cholesterol. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04177680.

Contains fulltext : 286841.pdf (Publisher’s version ) (Closed access) BACKGROUND: Resistant hypertension is associated with increased cardiovascular risk. The endothelin pathway has been implicated in the pathogenesis of hypertension, but it is currently not targeted therapeutically, thereby leaving this relevant pathophysiological pathway unopposed with currently available drugs. The aim of the study was to assess the blood pressure lowering efficacy of the dual endothelin antagonist aprocitentan in patients with resistant hypertension. METHODS: PRECISION was a multicentre, blinded, randomised, parallel-group, phase 3 study, which was done in hospitals or research centres in Europe, North America, Asia, and Australia. Patients were eligible for randomisation if their sitting systolic blood pressure was 140 mm Hg or higher despite taking standardised background therapy consisting of three antihypertensive drugs, including a diuretic. The study consisted of three sequential parts: part 1 was the 4-week double-blind, randomised, and placebo-controlled part, in which patients received aprocitentan 12·5 mg, aprocitentan 25 mg, or placebo in a 1:1:1 ratio; part 2 was a 32-week single (patient)-blind part, in which all patients received aprocitentan 25 mg; and part 3 was a 12-week double-blind, randomised, and placebo-controlled withdrawal part, in which patients were re-randomised to aprocitentan 25 mg or placebo in a 1:1 ratio. The primary and key secondary endpoints were changes in unattended office systolic blood pressure from baseline to week 4 and from withdrawal baseline to week 40, respectively. Secondary endpoints included 24-h ambulatory blood pressure changes. The study is registered on ClinicalTrials.gov, NCT03541174. FINDINGS: The PRECISION study was done from June 18, 2018, to April 25, 2022. 1965 individuals were screened and 730 were randomly assigned. Of these 730 patients, 704 (96%) completed part 1 of the study; of these, 613 (87%) completed part 2 and, of these, 577 (94%) completed part 3 of the study. The least square mean (SE) change in office systolic blood pressure at 4 weeks was -15·3 (SE 0·9) mm Hg for aprocitentan 12·5 mg, -15·2 (0·9) mm Hg for aprocitentan 25 mg, and -11·5 (0·9) mm Hg for placebo, for a difference versus placebo of -3·8 (1·3) mm Hg (97·5% CI -6·8 to -0·8, p=0·0042) and -3·7 (1·3) mm Hg (-6·7 to -0·8; p=0·0046), respectively. The respective difference for 24 h ambulatory systolic blood pressure was -4·2 mm Hg (95% CI -6·2 to -2·1) and -5·9 mm Hg (-7·9 to -3·8). After 4 weeks of withdrawal, office systolic blood pressure significantly increased with placebo versus aprocitentan (5·8 mm Hg, 95% CI 3·7 to 7·9, p

We present an Arctic aerosol optical depth (AOD) climatology and trend analysis for 2003–2019 spring and summertime periods derived from a combination of multi-agency aerosol reanalyses, remote sensing retrievals, and ground observations. This includes the U.S. Navy Aerosol Analysis and Prediction System ReAnalysis version 1 (NAAPS-RA v1), the NASA Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), and the Copernicus Atmosphere Monitoring Service ReAnalysis (CAMSRA). Space-borne remote sensing retrievals of AOD are considered from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Multi-angle Imaging SpectroRadiometer (MISR), and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). Ground-based data include sun photometer data from Aerosol Robotic Network (AERONET) sites and oceanic Maritime Aerosol Network (MAN) measurements. Aerosol reanalysis AODs and space-borne retrievals show consistent climatological spatial patterns and trends for both spring and summer seasons over the sub-Arctic (60–70° N). Consistent signs in the AOD trend are also found for the high Arctic (north of 70° N) from reanalyses. The aerosol reanalyses yield more consistent AOD results than climate models, verify well with AERONET, and corroborate complementary climatological and trend analysis. Speciated AODs are more variable than total AOD among the three reanalyses, and a little more so for March–May (MAM) than for June–August (JJA). Black Carbon (BC) AOD in the Arctic comes predominantly from biomass burning sources in both MAM and JJA, and biomass burning overwhelms anthropogenic sources in JJA for the study period. AOD exhibits a negative trend in the Arctic in MAM, and a positive trend in JJA during 2003–2019, due to an overall decrease in sulfate/anthropogenic pollutions, and a significant increase in biomass burning smoke in JJA. Interannual Arctic AOD variability is significantly large, driven by fine-mode, and specifically, biomass burning (BB) smoke, though more so in JJA than in MAM. Extreme AOD events during spring and summer in the Arctic, defined as AOD greater than the 95th percentile value, are mainly attributed to BB smoke transport events. Extreme AOD cases tend to occur later in the season (i.e., July and August, in the latter decade rather than spreading over April–August in the early decade during 2003–2019) corresponding to a shift to a later time in extreme boreal BB activities.

This study proposes a methodology to identify, evaluate and select parts, components and products within the railway environment that will benefit from the Fused Deposition Modelling Additive Manufacturing technology at the initial conceptual design phase. A review on the state-of-the-art in Multi-Criteria Decision-Making models is presented, focusing on the Fused Deposition Modelling Additive Manufacturing process. The criteria identified in the literature were used to develop a custom evaluation model for part selection specific to railway maintenance applications using the Analytic Hierarchy Process. The proposed methodology is validated using case studies from published literature and then applied to railway-specific case studies to determine its benefit using the Fused Deposition Modelling technology. The railway case studies present functional end-use 3D printed replacement parts, custom tooling and prototype products for railway infrastructure and rolling stock vehicles. Lastly, the proposed methodology was integrated into a program using Visual Basic and Microsoft Excel to assist novice railway engineers in identifying whether parts will benefit from the 3D printing process.

Genetic screens are used to identify genes involved in specific biological processes. An EMS mutagenesis screen in Drosophila melanogaster identified growth control phenotypes in the developing eye. One mutant line from this screen, H.3.2, was phenotypically characterized using the FLP/FRT system and genetically mapped by complementation analysis and genomic sequencing by undergraduate students participating in the multi-institution Fly-CURE consortium. H.3.2 was found to have a nonsense mutation in short stop (shot), anortholog of the mammalian spectraplakin dystonin (DST). shot and DST are involved in cytoskeletal organization and play roles during cell growth and proliferation.

The EphA2 receptor tyrosine kinase mediates ligand-induced canonical signaling associated with tumor suppression and ligand-independent noncanonical signaling implicated in tumor progression. Using time-resolved fluorescence spectroscopy in live cells, we find that unliganded EphA2 receptors pre-assemble into multimers, which is mediated by two symmetric and one asymmetric interfaces in the ectodomain. Upon ligand binding, EphA2 receptors are further assemble into large clusters that also requires the three interfaces. Functionally, disrupting either the symmetric or asymmetric contacts individually blocks the autorecycling of the EphA2 apo receptor. However, only symmetric contact disruption promotes noncanonical signaling and inhibits ligand-induced catalytic activation and endocytosis, which are associated with increased cell migration in vitro and reduced survival in a syngeneic murine glioblastoma model. Our results reveal the pivotal role of EphA2 assembly in dictating canonical vs. noncanonical signaling, and identify the precise molecular interfaces that mediate the formation of the EphA2 signaling clusters.

Background Antimicrobial resistance is a serious concern. Although the widespread use of antimicrobials in livestock has exacerbated the emergence and dissemination of antimicrobial resistance genes (ARG) in farm environments, little is known about whether antimicrobial use affects distribution of ARG in livestock systems. This study compared the distribution of microbiomes and resistomes (collections of ARG) across different farm sectors in dairy herds that differed in their use of antimicrobials. Feces from heifers, non-lactating, and lactating cows, manure storage, and soil from three conventional (antimicrobials used to treat cows) and three organic (no antimicrobials used for at least four years) farms in Pennsylvania were sampled. Samples were extracted for genomic DNA, processed, sequenced on the Illumina NextSeq platform, and analyzed for microbial community and resistome profiles using established procedures. Results Microbial communities and resistome profiles clustered by sample type across all farms. Overall, abundance and diversity of ARG in feces was significantly higher in conventional herds compared to organic herds. The ARG conferring resistance to betalactams, macrolide-lincosamide-streptogramin (MLS), and tetracyclines were significantly higher in fecal samples of dairy cows from conventional herds compared to organic herds. Regardless of farm type, all manure storage samples had greater diversity (albeit low abundance) of ARG conferring resistance to aminoglycosides, tetracyclines, MLS, multidrug resistance, and phenicol. All soil samples had lower abundance of ARG compared to feces, manure, and lagoon samples and were comprised of ARG conferring resistance to aminoglycosides, glycopeptides, and multi-drug resistance. The distribution of ARG is likely driven by the composition of microbiota in the respective sample types. Conclusions Antimicrobial use on farms significantly influenced specific groups of ARG in feces but not in manure storage or soil samples.

Immobilizing a signaling protein to guide cell behavior has been employed in a wide variety of studies. This approach draws inspiration from biology, where specific, affinity-based interactions between membrane receptors and immobilized proteins in the extracellular matrix guide many developmental and homeostatic processes. Synthetic immobilization approaches, however, do not necessarily recapitulate the in vivo signaling system and potentially lead to artificial receptor-ligand interactions. To investigate the effects of one example of engineered receptor-ligand interactions, we focus on the immobilization of interferon-γ (IFN-γ), which has been used to drive differentiation of neuronal stem cells (NSCs). To isolate the effect of ligand immobilization, we transfected Cos-7 cells with only interferon-γ receptor 1 (IFNγR1), not IFNγR2, so that the cells could bind IFN-γ, but were incapable of canonical signal transduction. We then exposed the cells to surfaces containing covalently immobilized IFN-γ and studied membrane morphology, receptor-ligand dynamics, and receptor activation. We found that exposing cells to immobilized, but not soluble IFN-γ, drove the formation of filopodia in both NSCs and Cos-7, showing that covalently immobilizing IFN-γ is enough to affect cell behavior, independently of canonical downstream signaling. Overall, this work suggests that synthetic growth factor immobilization can influence cell morphology beyond enhancing canonical cell responses through the prolonged signaling duration or spatial patterning enabled by protein immobilization. This suggests that differentiation of NSCs could be driven by canonical and non-canonical pathways when IFN-γ is covalently immobilized. This finding has broad implications for bioengineering approaches to guide cell behavior, as one ligand has the potential to impact multiple pathways even when cells lack the canonical signal transduction machinery.

The development of a robust microbiome is critical to the health of dairy calves, but relatively little is known about the progression of the microbiome through the weaning transition. In this study, fecal samples were obtained from ten female Holstein calves at 6 timepoints between 2–13 weeks of age. Calves were fed acidified milk until weaning at 8 weeks old and had access to starter grain throughout the study. Fecal samples were extracted for genomic DNA, PCR-amplified for the V1-V2 region of the 16S rRNA bacterial gene, sequenced on the Illumina MiSeq platform, and analyzed using the QIIME2 pipeline. Bacterial richness, estimated by number of observed species, and bacterial diversity, estimated by Shannon diversity index, both differed significantly between timepoints and both increased over time (P

Food waste is a matter intrinsically linked with the growing challenges of food security, resource and environmental sustainability, and climate change. In developed economies, the largest food waste stream occurs in the consumption stage at the end of the food chain. Current approaches for dealing with the wasted food have serious limitations. Historically, livestock animals had functioned as bio-processors, turning human-inedible or -undesirable food materials into meat, eggs, and milk. Contemporary treatment technologies can help convert the food waste into safe, nutritious, and value-added feed products. Recovering consumption-stage food waste for animal feeding is a viable solution that simultaneously addresses the issues of waste management, food security, resource conservation, and pollution and climate-change mitigation.

Background Secukinumab, a fully human monoclonal antibody that selectively neutralizes IL‐17A, has been shown to have significant efficacy and a favourable safety profile in the treatment of moderate‐to‐severe psoriasis and psoriatic arthritis. Objective To assess the efficacy and safety of secukinumab through 5 years of treatment in moderate‐to‐severe psoriasis. Methods In the core SCULPTURE study, Psoriasis Area and Severity Index (PASI) 75 responders at Week 12 continued receiving subcutaneous secukinumab until Year 1. Thereafter, patients entered the extension phase and continued treatment as per the core trial. Treatment was double‐blinded until the end of Year 3 and open‐label from Year 4. Here, we focus on the 300 mg fixed‐interval (every 4 weeks) treatment, the recommended per label dose. Efficacy data are primarily reported as observed, but multiple imputation (MI) and last observation carried forward (LOCF) techniques were also undertaken as supportive analyses. Results At Year 1, 168 patients entered the extension study and at the end of Year 5, 126 patients completed 300 mg (every 4 weeks) treatment. PASI 75/90/100 responses at Year 1 (88.9%, 68.5% and 43.8%, respectively) were sustained to Year 5 (88.5%, 66.4% and 41%). PASI responses were consistent regardless of the analysis undertaken (as observed, MI, or LOCF). The average improvement in mean PASI was approximately 90% through 5 years compared with core study baseline. DLQI (dermatology life quality index) 0/1 response also sustained through 5 years (72.7% at Year 1 and 65.5% at Year 5). The safety profile of secukinumab remained favourable, with no cumulative or unexpected safety concerns identified. Conclusion Secukinumab 300 mg treatment delivered high and sustained levels of skin clearance and improved quality of life through 5 years in patients with moderate‐to‐severe psoriasis. Favourable safety established in the secukinumab phase 2/3 programme was maintained through 5 years.

Translating current principles of language learning into effective classroom practice requires a nuanced understanding of the cognitive and social factors that shape how learners engage in instructional activity. In this paper, we identify four principles that represent a current theoretical consensus in the field, which we hope will guide practitioners as they assess their work: (1) All language use is purposeful, but not all language use is meaningful; (2) we learn by doing; (3) metalinguistic knowledge (still) matters; and (4) social contexts co-construct development. We then critique a common assumption that teachers can seamlessly implement pedagogical recommendations from available professional development opportunities and materials. Although the methods and techniques proposed through professional development may provide examples for implementation, only a deep personal understanding of principles can inform how they are most effectively realized in any local context. It is therefore the responsibility of teacher education and professional development providers to better articulate justifications for their recommendations and explore flexible adaptations in their application. It is also incumbent on researchers and theorists to better understand the realities of practitioners so that the principles they espouse will translate more readily into meaningful recommendations for practice.

The present review synthesizes published work from the global research community for the purpose of providing an overview of the state of knowledge regarding consumer food waste rate and characteristics. Our core interest is in primary data from field studies with direct measurements. We built a database consisting of 332 publications (1949–2019); data were extracted, weighted and normalized. Consumer food waste metrics were grouped into four categories: (i) food waste generation rate as kg cap−1 day−1 or kg cap−1 meal−1 from households, food services and schools; (ii) percent of food entering households or food services that was not eaten but discarded; (iii) food waste as a proportion of municipal solid waste stream; and (iv) physicochemical characteristics of food waste from the above sources, including pH, protein, lipids, gross energy and seven other parameters. Three tiers of analysis were performed: descriptive statistics, multiple pairwise comparisons, and interpretative analysis to discern trends and patterns. Methodologies used in individual studies for food waste rate determination varied a great deal, especially in participant number (5–25,000), study duration (1–700 days), and type of food waste collected and measured (edible vs. inedible; plate- vs. preparation- vs. serving-waste). Roughly half of the 53 parameters collectively analyzed did not conform to the normal distribution. Food waste rates were highly variable among studies. Very high and very low rates were reported in countries/regions of differing affluence. Moving forward on food waste reduction requires in-depth understanding of what drives high- vs. low-wasting behaviors to inform policies and enable actions.

Due to instrument sensitivities and algorithm detection limits, Level 2 (L2) Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) 532 nm aerosol extinction profile retrievals are often populated with retrieval fill values (RFVs), which indicate the absence of detectable levels of aerosol within the profile. In this study, using four years (2007–2008 and 2010–2011) of CALIOP Version 3 L2 aerosol data, the occurrence frequency of daytime CALIOP profiles containing all RFVs (all-RFV profiles) is studied. In the CALIOP data products, the aerosol optical thickness (AOT) of any all-RFV profile is reported as being zero, which may introduce a bias in CALIOP-based AOT climatologies. For this study, we derive revised estimates of AOT for all-RFV profiles using collocated Moderate Resolution Imaging Spectroradiometer (MODIS) Dark Target (DT) and, where available, Aerosol Robotic Network (AERONET) data. Globally, all-RFV profiles comprise roughly 71 % of all daytime CALIOP L2 aerosol profiles (i.e., including completely attenuated profiles), accounting for nearly half (45 %) of all daytime cloud-free L2 aerosol profiles. The mean collocated MODIS DT (AERONET) 550 nm AOT is found to be near 0.06 (0.08) for CALIOP all-RFV profiles. We further estimate a global mean aerosol extinction profile, a so-called noise floor, for CALIOP all-RFV profiles. The global mean CALIOP AOT is then recomputed by replacing RFV values with the derived noise floor values for both all-RFV and non-all-RFV profiles. This process yields an improvement in the agreement of CALIOP and MODIS over-ocean AOT.

In this proof-of-concept paper, we apply a bulk-mass-modeling method using observations from the NASA Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument for retrieving particulate matter (PM) concentration over the contiguous United States (CONUS) over a 2-year period (2008–2009). Different from previous approaches that rely on empirical relationships between aerosol optical depth (AOD) and PM2.5 (PM with particle diameters less than 2.5 µm), for the first time, we derive PM2.5 concentrations, during both daytime and nighttime, from near-surface CALIOP aerosol extinction retrievals using bulk mass extinction coefficients and model-based hygroscopicity. Preliminary results from this 2-year study conducted over the CONUS show a good agreement (r2∼0.48; mean bias of −3.3 µg m−3) between the averaged nighttime CALIOP-derived PM2.5 and ground-based PM2.5 (with a lower r2 of ∼0.21 for daytime; mean bias of −0.4 µg m−3), suggesting that PM concentrations can be obtained from active-based spaceborne observations with reasonable accuracy. Results from sensitivity studies suggest that accurate aerosol typing is needed for applying CALIOP measurements for PM2.5 studies. Lastly, the e-folding correlation length for surface PM2.5 is found to be around 600 km for the entire CONUS (∼300 km for western CONUS and ∼700 km for eastern CONUS), indicating that CALIOP observations, although sparse in spatial coverage, may still be applicable for PM2.5 studies.

Using nighttime observations from Visible/Infrared Imager/Radiometer Suite (VIIRS) Day/Night band (DNB), the characteristics of artificial light sources are evaluated as functions of observation conditions and incremental improvements are documented on nighttime aerosol retrievals using VIIRS DNB data on a regional scale. We find that the standard deviation of instantaneous radiance for a given artificial light source is strongly dependent upon the satellite viewing angle, but is weakly dependent on lunar fraction and lunar angle. Retrieval of nighttime aerosol optical thickness (AOT) based on the novel use of these artificial light sources is demonstrated for three selected regions (United States, Middle East, and India) during 2015. Reasonable agreements are found between nighttime AOTs from VIIRS DNB and temporally adjacent daytime AOTs from AErosol RObotic NETwork (AERONET) as well as from coincident nighttime AOT retrievals from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), indicating the potential of this method to begin filling critical gaps in diurnal AOT information at both regional and global scales. Issues related to cloud, snow, and ice contamination during the winter season, as well as data loss due to the misclassification of thick aerosol plumes as clouds, must be addressed to make the algorithm operationally robust.

Background Anxiety is considered a 'frequent' feature in the clinical criteria for Angelman syndrome; however, the nature and severity of anxiety symptoms have not been well characterised in this population. Anxiety behaviours, especially in response to separation from a preferred caregiver, have been described clinically but have not yet been explored empirically. Method This study used a combination of standardised and clinician-derived survey items to assess the frequency, nature and severity of behaviours associated with anxiety and separation distress in 100 individuals with Angelman syndrome. Family (e.g. income and maternal education) and individual (e.g. age, sex, genetic subtype, sleep difficulties and aggressive behaviours) variables were also gathered to assess possible predictors of higher anxiety levels. Approximately half of the sample was seen in clinic and assessed with standardised measures of development and daily functioning, allowing for an additional exploration of the association between anxiety symptoms and extent of cognitive impairment. Results Anxiety concerns were reported in 40% of the sample, almost 70% were reported to have a preferred caregiver and over half displayed distress when separated from that caregiver. Individuals with the deletion subtype and individuals who are younger were less likely to have anxiety behaviours. Sleep difficulties and aggressive behaviour consistently significantly predicted total anxiety, the latter suggesting a need for future studies to tease apart differences between anxiety and aggression or anger in this population. Conclusions Anxiety concerns, especially separation distress, are common in individuals with Angelman syndrome and represent an area of unmet need for this population.