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There is a growing understanding that secondary organic aerosol (SOA) can form through reactions in atmospheric waters (i.e., clouds, fogs, and aerosol water). In clouds and wet aerosols, water-soluble organic products of gas-phase photochemistry dissolve into the aqueous phase where they can react further (e.g., with OH radicals) to form low volatility products that are largely retained in the particle phase. Organic acids, oligomers and other products form via radical and non-radical reactions, including hemiacetal formation during droplet evaporation, acid/base catalysis, and reaction of organics with other constituents (e.g., NH4+). This paper provides an overview of SOA formation through aqueous chemistry, including atmospheric evidence for this process and a review of radical and non-radical chemistry, using glyoxal as a model precursor. Previously unreported analyses and new kinetic modeling are reported herein to support the discussion of radical chemistry. Results suggest that reactions with OH radicals tend to be faster and form more SOA than non-radical reactions. In clouds these reactions yield organic acids, whereas in wet aerosols they yield large multifunctional humic-like substances formed via radical-radical reactions and their O/C ratios are near 1.

Background: Physical activity is essential for chronic disease prevention, yet <40% of overweight/obese adults meet the national activity recommendations. For time-efficient counseling, clinicians need a brief, easy-to-use tool that reliably and validly assesses a full range of activity levels, and, most importantly, is sensitive to clinically meaningful changes in activity. The Stanford L eisure-Time Activity Cat egorical Item (L-Cat) is a single item comprising six descriptive categories ranging from inactive to very active. This novel methodological approach assesses national activity recommendations as well as multiple clinically relevant categories below and above the recommendations, and incorporates critical methodological principles that enhance psychometrics (reliability, validity and sensitivity to change). Methods: We evaluated the L-Cat’s psychometrics among 267 overweight/obese women who were asked to meet the national activity recommendations in a randomized behavioral weight-loss trial. Results: The L-Cat had excellent test–retest reliability ( κ =0.64, P <0.001) and adequate concurrent criterion validity; each L-Cat category at 6 months was associated with 1059 more daily pedometer steps (95% CI 712–1407, β =0.38, P <0.001) and 1.9% greater initial weight loss at 6 months (95% CI −2.4 to −1.3, β= −0.38, P <0.001). Of interest, L-Cat categories differentiated from each other in a dose-response gradient for steps and weight loss ( P s<0.05) with excellent face validity. The L-Cat was sensitive to change in response to the trial’s activity component. Women increased one L-Cat category at 6 months ( M =1.0±1.4, P <0.001); 55.8% met the recommendations at 6 months whereas 20.6% did at baseline ( P <0.001). Even among women not meeting the recommendations at both baseline and 6 months ( n =106), women who moved ⩾1 L-Cat categories at 6 months lost more weight than those who did not ( M =−4.6%, 95% CI −6.7 to −2.5, P <0.001). Conclusions: Given strong psychometrics, the L-Cat has timely potential for clinical use such as tracking activity changes via electronic medical records, especially among overweight/obese populations who are unable or unlikely to reach national recommendations.

The 5th edition of the Roma-BZCAT Multifrequency Catalogue of Blazars is available in a printed version and online at the ASDC website ( http://www.asdc.asi.it/bzcat ); it is also in the NED database. It presents several relevant changes with respect to the past editions which are briefly described in this paper.

Mass and energy exchanges between soil, plants and atmosphere control a number of key environmental processes involving hydrology, biota and climate. The understanding of these exchanges also play a critical role for practical purposes e.g. in precision agriculture. In this paper we present a methodology based on coupling innovative data collection and models in order to obtain quantitative estimates of the key parameters of such complex flow system. In particular we propose the use of hydro-geophysical monitoring via \"time-lapse\" electrical resistivity tomography (ERT) in conjunction with measurements of plant transpiration via sap flow and evapotranspiration (ET) from eddy covariance (EC). This abundance of data is fed to spatially distributed soil models in order to characterize the distribution of active roots. We conducted experiments in an orange orchard in eastern Sicily (Italy), characterized by the typical Mediterranean semi-arid climate. The subsoil dynamics, particularly influenced by irrigation and root uptake, were characterized mainly by the ERT set-up, consisting of 48 buried electrodes on 4 instrumented micro-boreholes (about 1.2 m deep) placed at the corners of a square (with about 1.3 m long sides) surrounding the orange tree, plus 24 mini-electrodes on the surface spaced 0.1 m on a square grid. During the monitoring, we collected repeated ERT and time domain reflectometry (TDR) soil moisture measurements, soil water sampling, sap flow measurements from the orange tree and EC data. We conducted a laboratory calibration of the soil electrical properties as a function of moisture content and porewater electrical conductivity. Irrigation, precipitation, sap flow and ET data are available allowing for knowledge of the system's long-term forcing conditions on the system. This information was used to calibrate a 1-D Richards' equation model representing the dynamics of the volume monitored via 3-D ERT. Information on the soil hydraulic properties was collected from laboratory and field experiments. The successful results of the calibrated modelling exercise allow for the quantification of the soil volume interested by root water uptake (RWU). This volume is much smaller (with a surface area less than 2 m2, and about 40 cm thick) than expected and assumed in the design of classical drip irrigation schemes that prove to be losing at least half of the irrigated water which is not taken up by the plants.

In core-collapse supernovae, titanium-44 (44Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed compact object. As such, it provides a direct probe of the supernova engine. Observations of supernova 1987A (SN1987A) have resolved the 67.87- and 78.32–kilo–electron volt emission lines from decay of 44Ti produced in the supernova explosion. These lines are narrow and redshifted with a Doppler velocity of ∼700 kilometers per second, direct evidence of large-scale asymmetry in the explosion.

Lafora disease (LD) is a fatal progressive epilepsy essentially caused by loss‐of‐function mutations in the glycogen phosphatase laforin or the ubiquitin E3 ligase malin. Glycogen in LD is hyperphosphorylated and poorly hydrosoluble. It precipitates and accumulates into neurotoxic Lafora bodies (LBs). The leading LD hypothesis that hyperphosphorylation causes the insolubility was recently challenged by the observation that phosphatase‐inactive laforin rescues the laforin‐deficient LD mouse model, apparently through correction of a general autophagy impairment. We were for the first time able to quantify brain glycogen phosphate. We also measured glycogen content and chain lengths, LBs, and autophagy markers in several laforin‐ or malin‐deficient mouse lines expressing phosphatase‐inactive laforin. We find that: (i) in laforin‐deficient mice, phosphatase‐inactive laforin corrects glycogen chain lengths, and not hyperphosphorylation, which leads to correction of glycogen amounts and prevention of LBs; (ii) in malin‐deficient mice, phosphatase‐inactive laforin confers no correction; (iii) general impairment of autophagy is not necessary in LD. We conclude that laforin's principle function is to control glycogen chain lengths, in a malin‐dependent fashion, and that loss of this control underlies LD. Synopsis Abnormal glycogen chain length distribution strictly correlates with glycogen accumulation and Lafora body (LB) formation in Lafora disease (LD). Against current hypotheses, neither glycogen hyperphosphorylation nor deficient general autophagy are prerequisites of the disease. By methodological advances chain length distribution (CLD) and phosphorylation of glycogen were determined in brain tissue confirming that overexpressed wild‐type laforin corrects the molecular phenotype in an LD mouse model. Phosphatase‐inactive laforin does not correct glycogen hyperphosphorylation in malin‐ and laforin‐deficient mice and prevents abnormal CLD and accumulation of glycogen as well as LB formation. Prevention of abnormal chain length distribution and accumulation of brain glycogen as well as LB formation by phosphatase‐inactive laforin is malin‐dependent as no rescue occurs in malin‐deficient mice. General impairment of autophagy is not necessary in LD as markers of autophagic flux are not changed in any of our LD mouse models. Laforin controls glycogen chain length distribution in a malin‐dependent fashion, and lack of this control leads to abnormal glycogen structure, glycogen accumulation, LB formation, hence to LD. Graphical Abstract Abnormal glycogen chain length distribution strictly correlates with glycogen accumulation and Lafora body (LB) formation in Lafora disease (LD). Against current hypotheses, neither glycogen hyperphosphorylation nor deficient general autophagy are prerequisites of the disease.

HERMES-Pathfinder is a space-borne mission based on a constellation of six nano-satellites flying in a low-Earth orbit. The 3U CubeSats, to be launched in early 2025, host miniaturized instruments with a hybrid Silicon Drift Detector/scintillator photodetector system, sensitive to both X-rays and gamma-rays. A seventh payload unit is installed onboard SpIRIT, an Australian-Italian nano-satellite developed by a consortium led by the University of Melbourne and launched in December 2023. The project aims at demonstrating the feasibility of Gamma-Ray Burst detection and localization using miniaturized instruments onboard nano-satellites. The HERMES flight model payloads were exposed to multiple well-known radioactive sources for spectroscopic calibration under controlled laboratory conditions. The analysis of the calibration data allows both to determine the detector parameters, necessary to map instrumental units to accurate energy measurements, and to assess the performance of the instruments. We report on these efforts and quantify features such as spectroscopic resolution and energy thresholds, at different temperatures and for all payloads of the constellation. Finally we review the performance of the HERMES payload as a photon counter, and discuss the strengths and the limitations of the architecture.

It is generally accepted that physical activity reduces the risk of coronary events. This study focused on whether walking, an activity of only moderate intensity, protects against coronary events in postmenopausal women. Walking was associated with risk reductions similar to those associated with vigorous exercise. The findings applied equally to both white women and black women. In postmenopausal women, brisk walking for at least 2.5 hours per week reduces the risk of coronary events. Physical activity has been associated with a reduced risk of cardiovascular disease in epidemiologic studies, 1 , 2 but data for women and members of minority ethnic groups have been sparse. Moreover, the specific role of walking, the most common form of exercise among women, 3 has been addressed only minimally. Federal guidelines from the Centers for Disease Control and Prevention and the American College of Sports Medicine, 4 as well as the Surgeon General's Report on Physical Activity and Health, 3 endorse at least 30 minutes of moderate-intensity physical activity on most, and preferably all, days of the week, in contrast to earlier guidelines . . .

Objective Adult polyglucosan body disease (APBD) is an adult‐onset neurological variant of glycogen storage disease type IV. APBD is caused by recessive mutations in the glycogen branching enzyme gene, and the consequent accumulation of poorly branched glycogen aggregates called polyglucosan bodies in the nervous system. There are presently no treatments for APBD. Here, we test whether downregulation of glycogen synthesis is therapeutic in a mouse model of the disease. Methods We characterized the effects of knocking out two pro‐glycogenic proteins in an APBD mouse model. APBD mice were crossed with mice deficient in glycogen synthase (GYS1), or mice deficient in protein phosphatase 1 regulatory subunit 3C (PPP1R3C), a protein involved in the activation of GYS1. Phenotypic and histological parameters were analyzed and glycogen was quantified. Results APBD mice deficient in GYS1 or PPP1R3C demonstrated improvements in life span, morphology, and behavioral assays of neuromuscular function. Histological analysis revealed a reduction in polyglucosan body accumulation and of astro‐ and micro‐gliosis in the brains of GYS1‐ and PPP1R3C‐deficient APBD mice. Brain glycogen quantification confirmed the reduction in abnormal glycogen accumulation. Analysis of skeletal muscle, heart, and liver found that GYS1 deficiency reduced polyglucosan body accumulation in all three tissues and PPP1R3C knockout reduced skeletal muscle polyglucosan bodies. Interpretation GYS1 and PPP1R3C are effective therapeutic targets in the APBD mouse model. These findings represent a critical step toward the development of a treatment for APBD and potentially other glycogen storage disease type IV patients.

Swift response The Swift satellite, launched in November last year, is designed to study γ-ray bursts (GRBs) as soon as they happen. GRBs are the most powerful explosions known in the Universe, and Swift's ability to study the early phases of the X-ray afterglow was expected to yield exciting results. Swift has now bagged its first two long GRBs: in both, the X-ray afterglow emission declined rapidly in the first few hundred seconds, then flattened out. The steep decline was unexpected, and neither it nor the spectral properties of the afterglow can be explained by current models. ‘Long’ γ-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which give rise to highly relativistic jets. Inhomogeneities in the expanding flow result in internal shock waves that are believed to produce the γ-rays we see 1 , 2 . As the jet travels further outward into the surrounding circumstellar medium, ‘external’ shocks create the afterglow emission seen in the X-ray, optical and radio bands 1 , 2 . Here we report observations of the early phases of the X-ray emission of five GRBs. Their X-ray light curves are characterised by a surprisingly rapid fall-off for the first few hundred seconds, followed by a less rapid decline lasting several hours. This steep decline, together with detailed spectral properties of two particular bursts, shows that violent shock interactions take place in the early jet outflows.