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Bioaerosols are an important subgroup of atmospheric aerosols, and microorganisms are a major component of bioaerosols. Microbial activity can affect climate change, human health and environmental processes. We developed a diacetate (FDA) hydrolysis method to measure microbial activity in bioaerosols. A large number of preliminary experiments were used to optimise the experimental conditions and guarantee the applicability of this assay to environmental bioaerosol samples. The level of microbial activity in the atmosphere in the Qingdao coastal region was measured using the FDA method in May and from September to December 2012. The microbial activity in bioaerosols varied from 10.7 to 85.8 ng/m sodium fluorescein, with an average of 30.2 ng/m. The microbial activity in bioaerosols displayed monthly variations, with the highest value in May. However, the activity showed no significant correlation with temperature, relative humidity and wind speed. Thus, further study is needed to elucidate the major factors and mechanisms that affect microbial activity in the atmosphere. [ABSTRACT FROM AUTHOR]

Coupled physical–biological modelling experiments were made for the period of 1995–2009 to analyse the spatial and interannual variability of nutrients and phytoplankton production in the Gulf of Maine (GOM). The physical model was the Finite-Volume Community Ocean Model (FVCOM) and the biological model was a Nitrogen, Phytoplankton, Zooplankton, and Detritus (NPZD) model. The simulation was carried out with realistic meteorological surface forcing, five major tidal constituents, river discharge, and observation-based open boundary conditions. The results were robust with comparison to SeaWiFS chlorophyll data and historical data of nitrogen. An Empirical Orthogonal Function analysis clearly identified two dominant modes in nutrient and phytoplankton dynamics: (1) sustained nutrient supply and phytoplankton production from spring through autumn, and (2) a dominating phytoplankton bloom in spring, relatively low production in summer, and a noticeable bloom in autumn. Mode 1 was a dominant feature in strong tidal energy dissipation regions such as the southwestern shelf of Nova Scotia, Georges Bank, Nantucket Shoals, the Bay of Fundy, and the coastal regions of GOM, where tidal pumping and mixing were the major drivers for the sustained nutrient supply, and primary production showed certain resilience with less interannual variability. Mode 2 was a characteristic in the deep Gulf, the offshore region of the Scotian Shelf, and in the open sea area, where the timing and amplitude of the spring phytoplankton bloom is essentially controlled by the salinity regime, and its interannual variability was significantly influenced by freshening events controlled by local and remote forcing. [ABSTRACT FROM PUBLISHER]

Bioaerosols were collected by using a six-stage bioaerosols sampler from September 2007 to August 2008 in the coastal region of Qingdao, China. The terrestrial and marine microbes (including bacteria and fungi) were analyzed in order to understand the distribution features of bioaerosols. The results show that the average monthly concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi and marine fungi are in the ranges of 80-615 CFU m, 91-468 CFU m, 76-647 CFU m and 231-1959 CFU m, respectively. The concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi, marine fungi and total microbes are the highest in each microbial category during fall, high in spring, and the lowest in the summer and winter. The bacterial particles are coarse in spring, autumn and winter. The sizes of fungal particle present the log-normal distribution in all the seasons. [ABSTRACT FROM AUTHOR]

In the present study, replicative lifespan and chronological lifespan assays of yeast were used to double-screen antiaging compounds from Gentiana rigescens Franch, a Chinese herb medicine. Inokosterone from G. rigescens Franch extended not only the replicative lifespan of K6001 yeast but also the chronological lifespan of YOM36 yeast. Furthermore, it can enhance the survival ability of mammalian cells. In order to understand the mechanism of action of this compound, this study focused on antioxidative stress and autophagy when performing the analysis. The increased cell survival rate under oxidative stress conditions, antioxidant enzyme activity and gene expression were observed in the inokosterone-treated groups. Meanwhile, the reactive oxygen species (ROS) and lipid peroxidation of yeast were obviously decreased. Additionally, the macroautophagy and mitophagy in YOM38-GFP-ATG8 yeast were increased upon inokosterone treatment, respectively. At the same time, the cleavage-free GFP from GFP-ATG8 in the cytoplasm and the ubiquitin of the mitochondria at the protein level were markedly enhanced after incubation with inokosterone. Furthermore, we investigated the effect of inokosterone on antioxidative stress and autophagy in mammalian cells, and the relationship between ROS and autophagy. The ROS, malondialdehyde (MDA) were significantly decreased, and the autophagosomes in mammalian cells were obviously increased after inokosterone treatment. The autophagosomes in ∆sod1 yeast with a K6001 background had no obvious changes, and the ROS and MDA of ∆sod1 yeast were increased compared with K6001 yeast. The increase of autophagosomes and the reduction of ROS and MDA in ∆sod1 yeast were observed after treatment with inokosterone. Meanwhile, the reduction of the ROS level and the increase of the SOD1 gene expression of K6001 yeast lacking autophagy were observed after treatment with inokosterone. In order to indicate whether the genes related to antioxidant enzymes and autophagy were involved in the antiaging effect of inokosterone, mutants of K6001 yeast were constructed to conduct a lifespan assay. The replicative lifespans of ∆sod1, ∆sod2, ∆uth1, ∆skn7, ∆gpx, ∆cat, ∆atg2, and ∆atg32 of K6001 yeast were not affected by inokosterone. These results suggest that inokosterone exerted an antiaging activity via antioxidative stress and increased autophagy activation; autophagy affected the ROS levels of yeast via the regulation of SOD1 gene expression. [ABSTRACT FROM AUTHOR]

The concentration and flux of biological aerosol particles over oceans are important for understanding the ecological implications of airborne microbes in marine ecosystems. Airborne microbes over oceans remain uncharacterized, especially the difference between those over the marginal seas and those over the open oceans. Atmospheric aerosol samples were collected over Qingdao (QD), the Yellow and Bohai Seas (YBS) and the Northwest Pacific Ocean (NWPO) during three cruises in the spring of 2014 and 2016. The total airborne microbes (TAM) in the samples were assessed based on microscope counts. The TAM concentration was (4.07 ± 1.42) × 105 cells·m−3 and (2.75 ± 0.91) × 105 cells·m−3 over the NWPO in 2014 and 2016, respectively, significantly lower than that over QD ((8.02 ± 4.04) × 105 cells·m−3 and (14.04 ± 23.95) × 105 cells·m−3 in 2014 and 2016, respectively) due to the continental source of microbes, but the TAM concentration over the NWPO in 2014 was significantly higher than that over the YBS (p < 0.01). The microbe concentration over the NWPO was affected by wind speed and direction, the horizontal offshore distance and the ratio of the distance over the sea to the total transport distance (RS), but the microbe concentration over the YBS was affected by air temperature, NO, NO 2 , the distance over the sea, the horizontal offshore distance and RS. Compared with those in the marine samples, the TAM in coastal samples was affected by many factors, such as air temperature, relative humidity, atmospheric pressure, PM 2.5 , PM 10 , SO 2 and O 3. A dust event significantly increased the concentration of TAM by a factor of 1.6–49 and changed the size distribution of TAM in the samples. The dry deposition flux of TAM was 8.83 × 107–5.12 × 108 cells·m−2·d−1 over the NWPO, close to the flux of 1.20 × 108–2.63 × 108 cells·m−2·d−1 over the YBS. Our results suggest that airborne microbes are input to the ocean via atmospheric deposition, which may have important impacts on marine ecosystems. [Display omitted] • Stronger marine microbe sources occur over the open ocean than over marginal seas due to wind. • Microbe size distribution varies depending on source and environmental factors. • Dust increased the microbe concentration and changed its size distribution. • TAM concentration was affected by air pollutants over the YBS and by wind over the NWPO. • TAM flux distribution over oceans mainly depends on concentration. [ABSTRACT FROM AUTHOR]

On June 1, 2009, Air France AF447 disappeared in the Equatorial Atlantic Ocean en route from Rio de Janeiro, Brazil, to Paris, France. On June 6-19, 2009, bodies and debris from the aircraft were recovered floating in the equatorial ocean. This paper describes efforts on using the global-local nested finite volume community ocean model (FVCOM) to model reversely the tracks of bodies and debris back to the time of the crash and to help searchers locate the cockpit voice and flight data recorders and learn why this tragic accident occurred. To validate the reliability and reality of FVCOM, eight surface drifters were deployed by the French Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile (BEA) near the last known position in early June 2010 for a period of 3 weeks. These drifter data were used to optimize the spatial and temporal correlation scales of the adaptive sampling data assimilation method of FVCOM. Applying an optimized FVCOM system to assimilate all available drifter- and float-tracking-derived currents in May-June 2009 under three different wind conditions, we reproduced the June 2009 current fields in the area near the LKP and used these fields to reversely track bodies and debris from locations where they were found to the time when the crash occurred. Possible locations for the crashed plane were suggested based on our model results and were made available to the French investigators and the Woods Hole Oceanographic Institution REMUS autonomous underwater vehicle Operations Group who successfully located the aircraft debris field in April 2011 on the seafloor at a depth of 3,900 m. [ABSTRACT FROM AUTHOR]

Abstract: The mating hormones α1 and α2 induce sexual reproduction of the phytopathogenic genus Phytophthora. To demonstrate the structural elements responsible to hormonal activity, 17 derivatives of α1 and α2 were synthesized and their hormonal activity (oospore-inducing activity) was evaluated. The terminal ester derivatives of α1 (diacetate and dibenzoate) retained the hormonal activity, whereas a dicarbamate derivative completely suppressed the activity. Even monocarbamates showed weak activities; among them the 1-O-carbamate was less active than 16-O-carbamate, suggesting that the 1-OH group is a little more important than 16-OH. Dihydro, dehydro, and demethyl derivatives exhibited the minimum level of activity. Surviving activity of 15-epi-α1 suggested a less importance of this stereochemistry. Contrary to α1, not only the terminal diacetate derivative but also monoacetates of α2 exhibited no or little activity. Among the monoacetates, 1-O-acetyl-α2 exhibited little yet relatively better activity than the others. No activity was observed for mono- and dicarbamoyl derivatives of α2. Dihydro α2 with the saturated double bond lost most of the activity. These findings suggest that both the mating hormones α1 and α2 require most of the functional (hydroxyl, keto, and olefinic) groups they possess in their natural form for inducing the sexual reproduction of Phytophthora. [Copyright &y& Elsevier]

n effort was made to couple FVCOM (a three-dimensional (3D), unstructured grid, Finite Volume Coastal Ocean Model) and FVCOM-SWAVE (an unstructured grid, finite-volume surface wave model) for the study of nearshore ocean processes such as tides, circulation, storm surge, waves, sediment transport, and morphological evolution. The coupling between FVCOM and FVCOM-SWAVE was achieved through incorporating 3D radiation stress, wave-current-sediment-related bottom boundary layer, sea surface stress parameterizations, and morphology process. FVCOM also includes a 3D sediment transport module. With accurate fitting of irregular coastlines, the model provides a unique tool to study sediment dynamics in coastal ocean, estuaries, and wetlands where local geometries are characterized by inlets, islands, and intertidal marsh zones. The model was validated by two standard benchmark tests: 1) spectral waves approaching a mild sloping beach and 2) morphological changes of seabed in an idealized tidal inlet. In Test 1, model results were compared with both analytical solutions and laboratory experiments. A further comparison was also made with the structured grid Regional Ocean Model System (ROMS), which provides an insight into the performance of the two models with the same open boundary forcing. [ABSTRACT FROM AUTHOR]

We have previously shown that a mixture of cerebrosides obtained from dried tubers of herb Typhonium giganteum Engl. plays a neuroprotective role in the ischemic brain through its effect on activation of BKCa channels. It is very curious to know whether a single pure cerebroside compound could activate the BKCa channel as well. This study explored the possible effects of pure cerebroside compounds, termitomycesphins A and B, on the BKCa channel activation. Both termitomycesphins A and B activated the BKCa channels at micromole concentration without significant difference. Termitomycesphin A increased the single channel open probability of the BKCa channels in a dose-dependent manner without modifying the single channel conductance. Termitomycesphin A activated BKCa channel more efficiently when it was applied to the cytoplasmic face of the membrane, suggesting that binding site for termitomycesphin A is located at the cytoplasmic side. Termitomycesphin A shifted the voltage-dependent activation curve to less positive membrane potentials and the Ca2++-dependent activation curve of the channel upwards, suggesting that termitomycesphin A could activate the channels even without intracellular free Ca2++. Furthermore, STREX-deleted BKCa channels were completely insensitive to termitomycesphin A, indicating that STREX domain is required for the activation of the BKCa channel. These data provide evidence that termitomycesphins are potent in stimulating the activity of the BKCa channels. As BKCa channels are associated with pathology of many diseases, termitomycesphins might be used as therapeutic agents for treating these diseases through its regulatory effect on the BKCa channels. [ABSTRACT FROM AUTHOR]

Abstract: The structured-grid surface wave model SWAN (Simulating Waves Nearshore) has been converted into an unstructured-grid finite-volume version (hereafter referred to as FVCOM-SWAVE) for use in coastal ocean regions with complex irregular geometry. The implementation is made using the Flux-Corrected Transport (FCT) algorithm in frequency space, the implicit Crank–Nicolson method in directional space and options of explicit or implicit second-order upwind finite-volume schemes in geographic space. FVCOM-SWAVE is validated using four idealized benchmark test problems with emphasis on numerical dispersion, wave-current interactions, wave propagation over a varying-bathymetry shallow water region, and the basic wave grow curves. Results demonstrate that in the rectangular geometric domain, the second-order finite-volume method used in FVCOM-SWAVE has the same accuracy as the third-order finite-difference method used in SWAN. FVCOM-SWAVE was then applied to simulate wind-induced surface waves on the US northeast shelf with a central focus in the Gulf of Maine and New England Shelf. Through improved geometric fitting of the complex irregular coastline, FVCOM-SWAVE was able to robustly capture the spatial and temporal variation of surface waves in both deep and shallow regions along the US northeast coast. [Copyright &y& Elsevier]