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In the framework of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx;http://charmex.lsce.ipsl.fr/) initiative, a field campaign took place in the western Mediterranean Basin between 10 June and 5 July 2013 within the ADRIMED (Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region) project. The scientific objectives of ADRIMED are the characterization of the most common ‘Mediterranean aerosols’ and their direct radiative forcing (column closure and regional scale). During 15–24 June a multi-intrusion dust event took place over the western and central Mediterranean Basin. Extra measurements were carried out by some EARLINET/ACTRIS (European Aerosol Research Lidar Network /Aerosols, Clouds, and Trace gases Research InfraStructure Network,http://www.actris.net/) lidar stations in Spain and Italy, in particular on 22 June in support to the flight over southern Italy of the Falcon 20 aircraft involved in the campaign. This article describes the physical and optical properties of dust observed at the different lidar stations in terms of dust plume centre of mass, optical depth, lidar ratio, and particle depolarization ratio. To link the differences found in the origin of dust plumes, the results are discussed on the basis of back-trajectories and air- and space-borne lidars. This work puts forward the collaboration between a European research infrastructure (ACTRIS) and an international project (ChArMEx) on topics of interest for both parties, and more generally for the atmospheric community. [ABSTRACT FROM AUTHOR]

In the framework of ACTRIS (Aerosols, Clouds, and Trace Gases Research Infrastructure Network) summer 2012 measurement campaign (8 June-17 July 2012), EARLINET organized and performed a controlled exercise of feasibility to demonstrate its potential to perform operational, coordinated measurements and deliver products in near-real time. Eleven lidar stations participated in the exercise which started on 9 July 2012 at 06:00 UT and ended 72 h later on 12 July at 06:00 UT. For the first time, the single calculus chain (SCC) - the common calculus chain developed within EARLINET for the automatic evaluation of lidar data from raw signals up to the final products - was used. All stations sent in real-time measurements of a 1 h duration to the SCC server in a predefined netcdf file format. The pre-processing of the data was performed in real time by the SCC, while the optical processing was performed in near-real time after the exercise ended. 98 and 79% of the files sent to SCC were successfully pre-processed and processed, respectively. Those percentages are quite large taking into account that no cloud screening was performed on the lidar data. The paper draws present and future SCC users' attention to the most critical parameters of the SCC product configuration and their possible optimal value but also to the limitations inherent to the raw data. The continuous use of SCC direct and derived products in heterogeneous conditions is used to demonstrate two potential applications of EARLINET infrastructure: the monitoring of a Saharan dust intrusion event and the evaluation of two dust transport models. The efforts made to define the measurements protocol and to configure properly the SCC pave the way for applying this protocol for specific applications such as the monitoring of special events, atmospheric modeling, climate research and calibration/ validation activities of spaceborne observations. [ABSTRACT FROM AUTHOR]

In the framework of ACTRIS summer 2012 measurement campaign (8 June-17 July 2012), EARLINET organized and performed a controlled exercise of feasibility to demonstrate its potential to perform operational, coordinated measurements and deliver products in near-real time. Eleven lidar stations participated to the exercise which started on 9 July 2012 at 06:00 UT and ended 72 h later on 12 July at 06:00 UT. For the first time the Single-Calculus Chain (SCC), the common calculus chain developed within EARLINET for the automatic evaluation of lidar data from raw signals up to the final products, was used. All stations sent in real time measurements of 1 h of duration to the SCC server in a predefined netcdf file format. The pre-processing of the data was performed in real time by the SCC while the optical processing was performed in near-real time after the exercise ended. 98 and 84% of the files sent to SCC were successfully pre-processed and processed, respectively. Those percentages are quite large taking into account that no cloud screening was performed on lidar data. The paper shows time series of continuous and homogeneously obtained products retrieved at different levels of the SCC: range-square corrected signals (pre-processing) and daytime backscatter and nighttime extinction coefficient profiles (optical processing), as well as combined plots of all direct and derived optical products. The derived products include backscatter- and extinction-related Ångström exponents, lidar ratios and color ratios. The combined plots reveal extremely valuable for aerosol classification. The efforts made to define the measurements protocol and to configure properly the SCC pave the way for applying this protocol for specific applications such as the monitoring of special events, atmospheric modelling, climate research and calibration/validation activities of spaceborne observations. [ABSTRACT FROM AUTHOR]

Ripening descriptors are the main factors that determine consumers' preferences of soft cheeses. Six descriptors were defined to represent the sensory changes in Camembert cheeses: Penicillium camemberti appearance, cheese odor and rind color, creamy underrind thickness and consistency, and core hardness. To evaluate the effects of the main process parameters on these descriptors, Camembert cheeses were ripened under different temperatures (8, 12, and 16°C) and relative humidity (RH; 88, 92, and 98%). The sensory descriptors were highly dependent on the temperature and RH used throughout ripening in a ripening chamber. All sensory descriptor changes could be explained by microorganism growth, pH, carbon substrate metabolism, and cheese moisture, as well as by microbial enzymatic activities. On d 40, at 8°C and 88% RH, all sensory descriptors scored the worst: the cheese was too dry, its odor and its color were similar to those of the unripe cheese, the underrind was driest, and the core was hardest. At 16°C and 98% RH, the odor was strongly ammonia and the color was dark brown, and the creamy underrind represented the entire thickness of the cheese but was completely runny, descriptors indicative of an over ripened cheese. Statistical analysis showed that the best ripening conditions to achieve an optimum balance between cheese sensory qualities and marketability were 13 ± 1°C and 94 ± 1% RH. [ABSTRACT FROM AUTHOR]

Green abalone (Haliotis fulgens) experienced severe biomass losses and massive mortality due to short-term marine climatic extremes. We studied green abalone behavior and energy expenditure in response to environmental stress. Acclimatized juveniles were subjected to hyperthermia (26°C), hypoxia (1.0 mg O2 L-1), the combination of both, and control conditions (18°C and oxygen saturation) using an automated system. The movement parameters of organisms were recorded by labeling and filming them, and the respiration rate was measured in hermetic chambers. There were differences in gross and net distance and velocity between the control and the combined stressors. Respiration was raised by hyperthermia, lowered by hypoxia, and further reduced by the combined stressors. All abalone that left the shelter during the night returned by daylight, while hypoxia and hyperthermia reduced this number. Research on environmental stress and movement strategies could lead to a more objective stress proxy. [ABSTRACT FROM AUTHOR]

To evaluate the effects of temperature and relative humidity (RH) on microbial and biochemical ripening kinetics, Camembert-type cheeses were prepared from pasteurized milk seeded with Kluyveromyces marxianus, Geotrichum candidum, Penicillium camemberti, and Brevibacterium aurantiacum. Microorganism growth and biochemical changes were studied under different ripening temperatures (8, 12, and 16°C) and RH (88, 92, and 98%). The central point runs (12°C, 92% RH) were both reproducible and repeatable, and for each microbial and biochemical parameter, 2 kinetic descriptors were defined. Temperature had significant effects on the growth of both K. marxianus and G. candidum, whereas RH did not affect it. Regardless of the temperature, at 98% RH the specific growth rate of P. camemberti spores was significantly higher [between 2 (8°C) and 106 times (16°C) higher]. However, at 16°C, the appearance of the rind was no longer suitable because mycelia were damaged. Brevibacterium aurantiacum growth depended on both temperature and RH. At 8°C under 88% RH, its growth was restricted (1.3 x 10 cfu/g), whereas at 16°C and 98% RH, its growth was favored, reaching 7.9 x 10 cfu/g, but the rind had a dark brown color after d 20. Temperature had a significant effect on carbon substrate consumption rates in the core as well as in the rind. In the rind, when temperature was 16°C rather than 8°C, the lactate consumption rate was approximately 2.9 times higher under 88% RH. Whatever the RH, temperature significantly affected the increase in rind pH (from 4.6 to 7.7 ± 0.2). At 8°C, an increase in rind pH was observed between d 6 and 9, whereas at 16°C, it was between d 2 and 3. Temperature and RH affected the increasing rate of the underrind thickness: at 16°C, half of the cheese thickness appeared ripened on d 14 (wrapping day). However, at 98% RH, the underrind was runny. In conclusion, some descriptors, such as yeast growth and the pH in the rind, depended solely on temperature. However, our findings highlight the fact that the interactions between temperature and RH played a role in P. camemberti sporulation, B. aurantiacum growth, carbon substrate consumption rates, and the thickening of the cheese underrind. Moreover, the best ripening conditions to achieve an optimum between microorganism growth and biochemical kinetics were 13°C and 94% RH. [ABSTRACT FROM AUTHOR]

Abstract: This paper addresses the issue of studying the viability theory, developed for model exploration purposes and in our example applied to the optimization of a food operation. The aim is to identify the whole set of viable trajectories for a given process. It focuses on the preservation of some specific properties of the system (constraints in the state space). On the basis of this set, a set of actions is identified and robustness is discussed. The proposed framework was adapted to a Camembert ripening model to identify the subset of the space state where almost one evolution starting in the subset remains indefinitely inside of the domain of some viability constraints, that makes it possible to reach a predefined quality target. The results were applied at the pilot scale and are discussed in this paper. The cheese ripening process was shortened by four days without significant changes in the microorganisms kinetics and a good sensory quality of the cheese. [Copyright &y& Elsevier]

Abstract: Modelling the cheese ripening process continues to remain a challenge because this process is a complex system. There is still lack of knowledge to understand the interactions taking place at different level of scale during the process. However, knowledge may be gathered from scientific and operational experts’ skills. Integrating this knowledge with knowledge extracted from experimental databases may allow a better understanding of the whole ripening process. This study presents an approach adapted from cognitive science to elicit and formalise experts’ knowledge about the camembert-type cheese ripening process. Next, the collected data were unified in a mathematical model based on a dynamic Bayesian network. This formalism makes it possible to integrate this heterogeneous data. The established model presents an average adequacy rate of about 85% with experimental data. [Copyright &y& Elsevier]

Modeling the cheese ripening process remains a challenge because of its complexity. We still lack the knowledge necessary to understand the interactions that take place at different levels of scale during the process. However, information may be gathered from expert knowledge. Combining this expertise with knowledge extracted from experimental databases may allow a better understanding of the entire ripening process. The aim of this study was to elicit expert knowledge and to check its validity to assess the evolution of organoleptic quality during a dynamic food process: Camembert cheese ripening. Experiments on a pilot scale were carried out at different temperatures and relative humidities to obtain contrasting ripening kinetics. During these experiments, macroscopic evolution was evaluated from an expert's point of view and instrumental measurements were carried out to simultaneously monitor microbiological, physicochemical, and biochemical kinetics. A correlation of 76% was established between the microbiological, physicochemical, and biochemical data and the sensory phases measured according to expert knowledge, highlighting the validity of the experts’ measurements. In the future, it is hoped that this expert knowledge may be integrated into food process models to build better decision-aid systems that will make it possible to preserve organoleptic qualities by linking them to other phenomena at the microscopic level. [ABSTRACT FROM AUTHOR]

Abstract: Food processes are systems featuring a large number of interacting microbiological and/or physicochemical components, whose aggregate activities are nonlinear and are responsible for the changes in food properties. As a result of time limits, financial constraints and scientific and technological obstacles, knowledge regarding food processes may be obtained from various sources of know-how such as expert operators, scientific theory, experimental trials etc. Faced with this fragmented and heterogeneous knowledge, it is difficult to implement mathematical models in the form of equations capable of representing and simulating all different phenomena that occur during the process. It is necessary to develop practical mathematical tools capable of integrating and unifying the knowledge puzzle in order to have a better understanding of the whole food process. With this aim in mind, the concept of dynamic Bayesian networks (DBNs) provides a practical mathematical formalism that makes it possible to describe complex dynamical systems tainted with uncertainty. It relies on probabilistic graphical models where the graphical structure of network defines highly-interacting sets between variables and probabilities take uncertainty pertaining to the system into account. To illustrate our approach, we focused on cheese ripening that still remains an ill-known and complicated process to control where capitalised knowledge is fragmented and incomplete. Based on the available knowledge, we propose a global representation/modelling and an explicit overview of the whole ripening process by means of dynamic Bayesian networks. That means we define a model allowing to describe a network of interactions taking place between variables at different scales (i.e. microbial behaviour as well as sensory development) during the ripening. Model has been tested with new experimental trials not available in the learning database. Simulated results are close to experimental data presenting an average adequacy rate of about 85% according to the admitted errors provided by experts highlighting its predictive character. The established model then presents the ability to predict the dynamics of sensory properties from the predicted microbial behaviour. [Copyright &y& Elsevier]

Regular aerosol backscatter measurements using an elastic-backscatter lidar were performed between May 2000 and December 2002 in Barcelona (Spain), within the framework of the European project EARLINET (European Aerosol Research Lidar Network). The mixed-layer depth was one of the major parameters to be retrieved. Three derivative methods have been tested in this complex coastal area using the range-squared-corrected lidar signal: (1) the minimum of its first derivative, (2) the minimum of its second derivative, and (3) the minimum of the first derivative of its logarithm. The second method was found to give statistically the best results when compared to radiosoundings, and was used to process the whole dataset. A number of 162 days and 660 profiles averaged over 30 min have been examined. Between 1000 and 1500 UTC, the mixed-layer depth oscillates between 300 and 1450 m in summer and between 390 and 1420 m in winter. The standard deviation for this portion of the day is 180 and 256 m, respectively, in summer and winter. In summer, low heights (mainly limited to 400–800 m) are associated with large mesoscale compensatory subsidence over the sea and to the thermal internal boundary-layer formation. The strong coastal and orographic influences and the climatological settling of Barcelona determine the complexity of the boundary-layer dynamics and the high heterogeneity of the lidar signals. In many cases, single lidar analyses do not allow an unambiguous determination of the mixed-layer depth. Two diurnal cycle measurements are discussed together with synoptic maps, backtrajectories and radiosoundings in order to outline the complexity of the area and the limitations of the methods. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the level of specialization of the symbiotic association between an entomopathogenic nematode ( Steinernema carpocapsae) and its mutualistic native bacterium ( Xenorhabdus nematophila). We made experimental combinations on an insect host where nematodes were associated with non-native symbionts belonging to the same species as the native symbiont, to the same genus or even to a different genus of bacteria. All non-native strains are mutualistically associated with congeneric entomopathogenic nematode species in nature. We show that some of the non-native bacterial strains are pathogenic for S. carpocapsae. When the phylogenetic relationships between the bacterial strains was evaluated, we found a clear negative correlation between the effect a bacterium has on nematode fitness and its phylogenetic distance to the native bacteria of this nematode. Moreover, only symbionts that were phylogenetically closely related to the native bacterial strain were transmitted. These results suggest that co-evolution between the partners has led to a high level of specialization in this mutualism, which effectively prevents horizontal transmission. The pathogenicity of some non-native bacterial strains against S. carpocapsae could result from the incapacity of the nematode to resist specific virulence factors produced by these bacteria. [ABSTRACT FROM AUTHOR]

The use of a shortwave infrared (SWIR) spectroradiometer as a solar radiometer is presented. The radiometer collects 1024 channels of data over the spectral range of 1.1--2.5 microm. The system was tested by applying the Langley method to data collected at a high altitude site on two consecutive days. Data processed for the 1.15--1.32- microm and 1.47--1.75-microm spectral intervals show temporal results similar to those obtained with a well-understood, visible, and near-infrared radiometer having 10 channels in the 0.38--1.03- microm spectral range. A modified Langley method was used for spectral regions where strong water vapor absorption invalidates the Langley method. It is estimated that the exoatmospheric intercept of the spectroradiometer was determined to better than 4% in nonabsorption regions between 1.15 and 1.75 microm and to better than 5% for a large portion of the 1.38- microm absorption band. These results, in addition to the agreement between the shortwave, and the visible and near-infrared radiometers, imply that the SWIR system operates well as a solar radiometer. The spectral optical depths from one day were used to determine a power-law aerosol size distribution using data from both the visible and near-infrared, and the shortwave infrared. The exponent derived for this power law differed from that obtained by using only the visible and near-infrared by 6%. Aerosol optical depths in the shortwave infrared derived from the visible and near-infrared results differed from the measured values by 0.005 at an optical depth of 0.016 and wavelength of 1.66 microm. [ABSTRACT FROM AUTHOR]

During the 2017 record-breaking burning season in Canada/United States, intense wild fires raged during the first week of September in the Pacific northwestern region (British Columbia, Alberta, Washington, Oregon, Idaho, Montana and northern California) burning mostly temperate coniferous forests. The heavy loads of smoke particles emitted in the atmosphere reached the Iberian Peninsula (IP) a few days later on 7 and 8 September. Satellite imagery allows to identify two main smoke clouds emitted during two different periods that were injected and transported in the atmosphere at several altitude levels. Columnar properties on 7 and 8 September at two Aerosol Robotic Network (AERONET) mid-altitude, background sites in northern and southern Spain are: aerosol optical depth (AOD) at 440 nm up to 0.62, Ångström exponent of 1.6–1.7, large dominance of small particles (fine mode fraction >0.88), low absorption AOD at 440 nm (<0.008) and large single scattering albedo at 440 nm (>0.98). Profiles from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) show the presence of smoke particles in the stratosphere during the transport, whereas the smoke is only observed in the troposphere at its arrival over the IP. Portuguese and Spanish ground lidar stations from the European Aerosol Research Lidar Network/Aerosols, Clouds, and Trace gases Research InfraStructure Network (EARLINET/ACTRIS) and the Micro-Pulse Lidar NETwork (MPLNET) reveal smoke plumes with different properties: particle depolarization ratio and color ratio, respectively, of 0.05 and 2.5 in the mid troposphere (5–9 km) and of 0.10 and 3.0 in the upper troposphere (10–13 km). In the mid troposphere the particle depolarization ratio does not seem time-dependent during the transport whereas the color ratio seems to increase (larger particles sediment first). To analyze the horizontal and vertical transport of the smoke from its origin to the IP, particle dispersion modelling is performed with the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) parameterized with satellite-derived biomass burning emission estimates from the Global Fire Assimilation System (GFAS) of the Copernicus Atmosphere Monitoring Service (CAMS). Three compounds are simulated: carbon monoxide, black carbon and organic carbon. The results show that the first smoke plume which travels slowly reaches rapidly (~1 day) the upper troposphere and lower stratosphere (UTLS) but also shows evidence of large scale horizontal dispersion, while the second plume, entrained by strong subtropical jets, reaches the upper troposphere much slower (~2.5 days). Observations and dispersion modelling all together suggest that particle depolarization properties are enhanced during their vertical transport from the mid to the upper troposphere. • Long-range transport of a smoke plume from northern America to Europe • Time-space monitoring with ground and space-borne lidars of a smoke plume • Injection of smoke particles up to the upper troposphere (<13 km) • Dispersion model parameterization with satellite-based biomass burning estimates • Possible rationales for the smoke absorption and depolarization properties observed [ABSTRACT FROM AUTHOR]

Les infections materno-foetales (IMF) à Streptococcus agalactiae (SGB) sont rares mais de pronostic grave. L’hémoculture périphérique est le test diagnostic principal, mais le résultat est peu sensible et tardif (24–48h). Des techniques de biologie moléculaire automatisée, rapides et sensibles ont été validées sur écouvillon dans le diagnostic du portage vaginal de SGB per partum. Objectif Etudier les performances diagnostiques de la PCR automatisée pour la détection du SGB dans le sang. Matériels et méthodes Analyse par PCR automatisée (GENEXPERT®), comparativement à la culture, de 65 échantillons de sang de cordon inoculés avec une quantité croissante de SGB ; puis du sang de cordon de 24 nouveau-nés suspects d’IMF à SGB et 74 témoins non infectés. Résultats principaux Détection par PCR de 10 2 CFU/mL et 10 6 CFU/mL dans 23,8% et 100% des cas respectivement. 4% des NN suspects d’IMF avaient une hémoculture positive à SGB alors que la PCR était négative (SE et VPP 0, SP 100% (IC95% [99,97-100,02]), VPN 94,4% (IC95% [89,4–99,4]). Conclusions Les performances diagnostiques du GENEXPERT® sont insuffisantes pour mettre en évidence une bactériémie anténatale à SGB sur sang de cordon. Cette technique doit être perfectionnée afin de faciliter le diagnostic précoce d’IMF à SGB. [ABSTRACT FROM AUTHOR]

Vertically transmitted symbionts can distort their host's reproduction to increase their own transmission. In Wolbachia and some other symbionts, a particular distortion of this sort is feminization, whereby genetic males, which cannot transmit symbionts, are converted during development into functional females, which do transmit symbionts when they reproduce. In this work, we propose a model to study how feminization intensity (i.e. penetrance) can evolve under different ecological constraints in WZ/ZZ hosts. More specifically, our model incorporates both imperfect vertical and horizontal transmission modes. The model shows that for most parameter values feminizing symbionts drive genetic females to extinction, which in turn favours the evolution of maximum feminization penetrance. Once genetic females are extinct, the actual value of feminization penetrance never depends on the efficiency of vertical transmission. Instead, the model shows that in conditions where the reproductive rate is high at demographic equilibrium, higher feminization levels are favoured. One consequence of this can be, for example, that evolutionarily stable feminization penetrance increases with the host's natural death rate, just as the virulence is predicted to do with the host's natural death rate in classic epidemiological models. Finally, we found that horizontal transmission had no impact on how feminization penetrance evolved when genetic females were extinct. However, horizontal transmission can permit genetic females to coexist with symbionts and, in this case, we demonstrate that the presence of genetic females selects symbionts for lower feminization penetrance. [ABSTRACT FROM AUTHOR]

Antipsychotic-induced weight gain has emerged as a serious complication in the treatment of patients with most antipsychotics. We have conducted the first in-depth examination of dopamine receptor genes in antipsychotic-induced weight gain. A total of 206 patients (139 of European descent and 56 African Americans) who underwent treatment for chronic schizophrenia or schizoaffective disorder were evaluated after on average over 6 weeks of treatment. Thirty-six tag single nucleotide polymorphisms (SNPs) and one variable-number tandem repeat, spanning the five dopamine receptor genes (DRD1-DRD5) were analyzed. In the total sample, we found a nominally significant association between the DRD2 rs1079598 marker and weight change using a cutoff of 7% gain (P=0.03). When stratifying the sample according to ethnicity and antipsychotics with highest risk for weight gain, we found significant associations in three DRD2 SNPs: rs6277 (C957T), rs1079598 and rs1800497 (TaqIA). The other genes were primarily negative. We provide evidence that dopamine receptor DRD2 gene variants might be associated with antipsychotic-induced weight gain in chronic schizophrenia patients. [ABSTRACT FROM AUTHOR]

Competition among different parasite genotypes within a host is predicted to affect virulence. The direction of this effect, however, depends critically on the mechanisms that parasites use to compete or to cooperate with each other. One mechanism that bacteria use to compete with each other is via the production of bacteria-killing toxins, called bacteriocins. This warfare among parasites within a host is predicted to reduce the rate of host exploitation, resulting in lower virulence. By contrast, if parasites within a host are highly related, there could be a reduction in within-host conflict, increasing virulence. We examined this idea by allowing an insect-parasitic nematode ( Steinernema carpocapsae) and its symbiotic bacteria ( Xenorhabdus nematophila) to evolve for 20 passages under two different migration treatments (low and high). We found that host mortality rates were higher in the low-migration treatment when compared with the high-migration treatment. In addition, bacteria isolated from the same insect host inhibited each other’s growth, but only in the high-migration treatment. These results show that population structure and interactions among parasites within hosts can be critical to understanding virulence. [ABSTRACT FROM AUTHOR]

In marine ectotherms, reproduction is an energetically expensive process that affects their thermal window tolerance. For most species, the impacts of hyperthermia during gametogenesis have still not been addressed. Our aim was to assess the metabolic response of adult Nodipecten subnodosus scallops to thermal challenges at early development (spring) and advanced gonad maturation (summer). Scallops collected in both seasons were exposed to acute hyperthermia (26 and 30 °C, 24 h), maintaining a group of scallops at acclimation temperature (22 °C) as a control condition. During the summer, relatively low activity of hexokinase (HK), as well as low levels of ATP and GTP were found in the adductor muscle, suggesting a shift in energy investment for reproduction, although arginine phosphate (ArgP) levels were higher in summer scallops. Hyperthermia (30 °C) induced an increased energy expenditure reflected by a transitory enhanced oxygen consumption (VO2) and relatively high activities of HK and arginine kinase (AK). Moreover, a slight decrease in adenylic energy charge (AEC) was partially compensated by a decrease in ArgP. An increase in nucleotide by-products inosine monophosphate (IMP) and hypoxanthine (HX) indicated a thermal stress at 30 °C. Some of the responses to acute hyperthermia were more pronounced at advanced maturation stages (summer scallops), indicating a possible lack of energy balance, with possible implications in animals challenged to global warming scenario. [ABSTRACT FROM AUTHOR]

Three volcanic plumes were detected during the Tajogaite volcano eruptive activity (Canary Islands, Spain, September–December 2021) over the Iberian Peninsula. The spatiotemporal evolution of these events is characterised by combining passive satellite remote sensing and ground-based lidar and sun-photometer systems. The inversion algorithm GRASP is used with a suite of ground-based remote sensing instruments such as lidar/ceilometer and sun-photometer from eight sites at different locations throughout the Iberian Peninsula. Satellite observations showed that the volcanic ash plumes remained nearby the Canary Islands covering a mean area of 120 ± 202 km2 during the whole period of eruptive activity and that sulphur dioxide plumes reached the Iberian Peninsula. Remote sensing observations showed that the three events were mainly composed of sulphates, which were transported from the volcano into the free troposphere. The high backscatter-related Ångström exponents for wavelengths 532–1064 nm (1.17 ± 0.20 to 1.40 ± 0.24) and low particle depolarization ratios (0.08 ± 0.02 to 0.09 ± 0.02), measured by the multi-wavelength Raman lidar, hinted at the presence of spherical small particles. The layer aerosol optical depth at 532 nm (AOD L 532) obtained from lidar measurements contributed between 49% and 82% to the AERONET total column AOD at 532 nm in event II (11–13 October). According to the GRASP retrievals, the layer aerosol optical depth at 440 nm (AOD L 440) was higher in all sites during event II with values between 0.097 (Badajoz) and 0.233 (Guadiana-UGR) and lower in event III (19–21 October) varying between 0.003 (Granada) and 0.026 (Évora). Compared with the GRASP retrievals of total column AOD at 440 nm, the AOD L 440 had contributions between 21% and 52% during event II. In the event I (25–28 September), the mean volume concentrations (VC) varied between 5 ± 4 μm3cm−3 (El-Arenosillo/Huelva) and 17 ± 10 μm3cm−3 (Guadiana-UGR), while in event II this variation was from 11 ± 7 μm3cm−3 (Badajoz) to 27 ± 10 μm3cm−3 (Guadiana-UGR). Due to the impact of volcanic events on atmospheric and economic fields, such as radiative forcing and airspace security, a proper characterization is required. This work undertakes it using advanced instrumentation and methods. • Ash clouds remain near the volcano during all activity period. • Volcanic sulphates are identified over Iberian Peninsula from remote sensing. • Tropospheric volcanic layers are characterised by low depolarizing particles. • Volcanic aerosol properties are retrieved from GRASP algorithm. [ABSTRACT FROM AUTHOR]

With ongoing climate change, rising ocean temperature is usually accompanied by falling oxygen levels (hypoxia) and increasing CO 2 concentration (hypercapnia). Both drivers may impose constraints on physiological mechanisms that define thermal limits resulting in increased vulnerability towards warming in marine ectotherms. The present study aimed to detect differences in thermal tolerance by investigating the underlying metabolic responses in the green abalone ( Haliotis fulgens ) under conditions of hypoxia and hypercapnia. Juvenile abalones were exposed to a temperature ramp (+ 3 °C day − 1 ) under hypoxia (50% air saturation) and hypercapnia (~ 1000 μatm p CO 2 ), both individually and in combination. Impacts on energy metabolism were assessed by analyzing whole animal respiration rates and metabolic profiles of gills and hepatopancreas via 1 H NMR spectroscopy. While hypercapnia had a minor impact on the results of the temperature treatment, hypoxia strongly increased the vulnerability to warming, indicated by respiration rates falling below values expected from an exponential increase and by the onset of anaerobic metabolism suggesting a downward shift of the upper critical temperature. Warming under combined hypoxia and hypercapnia elicited a severe change in metabolism involving a strong accumulation of amino acids, osmolytes and anaerobic end products at intermediate temperatures, followed by declining concentrations at warmer temperatures. This matched the limited capacity to increase metabolic rate, loss of attachment and mortality observed under these conditions suggesting a strong narrowing of the thermal window. In all cases, the accumulation of free amino acids identified proteins as a significant energy source during warming stress. [ABSTRACT FROM AUTHOR]

High temperature increases energy demand in ectotherms, limiting their physiological capability to cope with hypoxic events. The present study aimed to assess the metabolic tolerance of juvenile Nodipecten subnodosus scallops to acute hyperthermia combined with moderate hypoxia. A previous study showed that juveniles exhibited a high upper temperature limit (32 °C), but the responses of juveniles to combined hyperthermia and low dissolved oxygen are unknown. Scallops were exposed to control conditions (treatment C: 22 °C, ∼7.1 mg O 2 L−1 or PO 2 156.9 mmHg), acute hyperthermia under normoxia (treatment T: 30 °C, ∼6.0 mg O 2 L−1 or PO 2 150.9 mmHg) or acute hyperthermia plus hypoxia (treatment TH: 30 °C, ∼2.5 mg O 2 L−1 or PO 2 62.5 mmHg) for 18 h. In T, juveniles exhibited an enhanced oxygen consumption, together with a decrease in adenylate energy charge (AEC) and arginine phosphate (ArgP), and with no changes in metabolic enzyme activity in the muscle. In TH, scallops maintained similar AEC and ArgP levels in muscle as those observed in T treatment. This response occurred along with the accumulation of inosine monophosphate and hypoxanthine. Besides, reduced citrate synthase and pyruvate kinase activities, enhanced hexokinase activity, and a higher octopine dehydrogenase/lactate dehydrogenase ratio in the mantle indicated the onset of anaerobiosis in TH. These responses indicate that juvenile scallops showed tissue-specific compensatory responses regarding their energy balance under moderate hypoxia at high temperatures. Our results give an insight into the tolerance limit of this species to combined hyperthermia and hypoxia in its northern limit of distribution. [Display omitted] • Oxygen consumption increases at high temperatures, a response affected by hypoxia. • Adenylate energy charge decreases, buffered by phosphagen hydrolysis and adenylate kinase. • Tissue-specific responses of metabolic enzyme activity under hyperthermia and hypoxia. [ABSTRACT FROM AUTHOR]

Hollow spheres made of BiTe nanoplatelets were successfully synthesized using a low temperature, wet chemical synthesis route. By using a one-pot synthesis, large quantities of microspheres, arranged in a gypsum flower manner, can be obtained in about 1 h. The mechanism leading to such a particular morphology has been deeply studied by both solid and solution characterization techniques (X-ray diffraction, scanning and transmission electron microscopy, X-ray fluorescence, H nuclear magnetic resonance spectroscopy) which were carried out at different stages of the synthesis. The key points are the generation of alcanethiol-in-polyol droplets and the subsequent in situ controlled interfacial reaction between Te and Bi precursors. The Te(IV) ions present in the alcanethiol phase are initially reduced into Te(0) by decanethiol. The Bi(III) ions initially dissolved in the polyol phase are then reduced at the decanethiol/polyol interface, resulting in the progressive growth of BiTe hexagonal nanoplatelets at the outer surface of the pristine Te(0) sphere. [ABSTRACT FROM AUTHOR]

Abstract: The experimental campaign “Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in Spain” (DAURE) took place in a urban (Barcelona city) and a rural (the Montseny Natural Park) Spanish sites. Its main objective was to study the formation and transport processes of particulate matter in the region during winter and summer time. This paper presents a description of the meteorological conditions during the campaign by means of meteorological observations, high-resolution mesoscale meteorological modelling and backward Lagrangian particle dispersion simulations. Modelling results are in agreement with observations and provide a valuable tool for characterizing transport patterns in relation to episodes of air pollution. An objective classification of the synoptic conditions and a classification of the main local dispersion patterns is presented and discussed. Additionally, the measured PM1 and PM10 levels in both urban and rural sites are discussed and related to the meteorological conditions observed. [Copyright &y& Elsevier]

The solar background illumination has a strong effect on CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) measurements, leading to a decrease in the signal-to-noise ratio of the lidar signal. Because of this, CALIOP level 2 data algorithms might be limited in the retrieval of the properties of the aerosols in the atmosphere. In this work, we present a methodology that combines CALIOP level 1 data with AERONET (Aerosol RObotic NETwork) measurements to retrieve aerosol extinction profiles and li-dar ratios in daytime conditions. In this way, we fulfill a two-fold objective: first, we obtain more accurate daytime aerosol information; second, we supplement column integrated measurements from AERONET sun photometers with information about the vertical distribution of aerosols. The methodology has been applied to Burjassot (39.30° N, 0.25° W) and Barcelona (41.39° N, 2.11° E) AERONET stations in the Mediterranean coast of Spain in the period from June 2006 to September 2011. We have found good agreement for the extinction profiles in several study cases of ground lidar measurements in Barcelona, coincident with CALIOP overpasses. Finally, the methodology has proved to be useful for the study of special episodes such as Saharan dust outbreaks [ABSTRACT FROM AUTHOR]

Total backscatter-coefficient inversion error bounds for the two-component lidar inversion algorithm (so-called Fernald's or Klett-Fernald-Sasano's method) are derived in analytical form in response to the following three error sources: 1) the measurement noise; 2) the user uncertainty in the backscatter-coefficient calibration; and 3) the aerosol extinction-to-backscatter ratio. The following two different types of error bounds are presented: 1) approximate error bounds using first-order error propagation and 2) exact error bounds using a total-increment method. Both error bounds are formulated in explicit analytical form, which is of advantage for practical physical sensitivity analysis and computational implementation. A Monte Carlo approach is used to validate the error bounds at 355-, 532-, and 1064-nm wavelengths. [ABSTRACT FROM AUTHOR]

Abstract: Aerosol transport simulations within Europe were performed with the regional transport model COSMO-MUSCAT for two different time periods, July 19–26, 2006 and February 16–26, 2007. Simulated PM 2.5, backscatter profiles and aerosol optical depths (AODs) were compared to observations, showing good agreements in magnitude, shape and day-to-day variations. Maximum AODs (>0.4) were found over Middle Europe and minimum AODs (<0.13) over the ocean during both time periods, corresponding to regions of high (PM 2.5 > 10 μg m−3) and low (PM 2.5 < 4.0 μg m−3) concentration near the surface. Vertical aerosol distributions were evaluated with lidar measurements from the EARLINET ground network and CALIPSO satellite retrievals. The characteristic vertical distribution and the differences for the summer and the winter cases were represented well by the regional model. Mean differences between −5.0 × 10−7 to−2.0 × 10−7 m−1 sr−1 (summer case) and −2.3 × 10−6 to 1.0 × 10−6 m−1 sr−1 (winter case) from 0.0 to 2.5 km altitude were found between observed (space-based lidar) and simulated backscatter coefficients. For the cases that were investigated in this study different prescriptions of the vertical distribution at the lateral model boundaries resulted in only small differences in aerosol distributions within the interior of the model region. [Copyright &y& Elsevier]

Coevolution in mutualistic symbiosis can yield, because the interacting partners share common interests, to coadaptation: hosts perform better when associated with symbionts of their own locality than with others coming from more distant places. However, as the two partners of a symbiosis might also experience conflicts over part of their life cycle, coadaptation might not occur for all life-history traits. We investigated this issue in symbiotic systems where nematodes ( Steinernema) and bacteria ( Xenorhabdus) reproduce in insects they have both contributed to kill. Newborn infective juveniles (IJs) that carry bacteria in their intestine then disperse from the insect cadaver in search of a new host to infect. We ran experiments where nematodes coinfect insects with bacteria that differ from their native symbiont. In both Steinernema carpocapsae/ Xenorhabdus nematophila and Steinernema feltiae/ Xenorhabdus bovienii symbioses, we detected an overall specificity which favours the hypothesis of a fine-tuned co-adaptation process. However, we also found that the life-history traits involved in specificity strongly differ between the two model systems: when associated with strains that differ too much from their native symbionts, S. carpocapsae has low parasitic success, whereas S. feltiae has low survival in dispersal stage. [ABSTRACT FROM AUTHOR]