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Among the various possible structural modifications spiropyrans may be subject to, ones containing alkyl sulfonates groups are commonly classified as photoacids. Both alkyl sulfonates spiropyrans named SON and SOH were structurally characterized and their acido- and photochromic properties were studied by UV–visible spectroscopy. Electrospun poly-ε-caprolactone (PCL) fibers were obtained, in which SON or SOH were incorporated with the goal of detecting acid and base vapors. PCL fibers containing the derivatives SON and SOH were successfully obtained (0.8 μm range), capable of acting as colorimetric vapor sensors according to the acidochromic properties of the spiropyrans. PCL-SON fibers presented quick vapor sensing capability, with colorimetric change within 10 s of exposure. Scanning electronic microscopy was crucial to characterize the morphology of these fibers before and after being used in the sensing process. This material could be reversibly reutilized in the sensing of acids and bases vapors according to the results presented. Graphical abstract Macroscopic color change for electrospun fibers based on acid or base vapors

The results from a carefully implemented GPS analysis, using a strategy adapted to determine accurate vertical station velocities, are presented. The stochastic properties of our globally distributed GPS position time series were inferred, allowing the computation of reliable velocity uncertainties. Most uncertainties were several times smaller than the 1–3 mm/yr global sea level change, and hence the vertical velocities could be applied to correct the long tide gauge records for land motion. The sea level trends obtained in the ITRF2005 reference frame are more consistent than in the ITRF2000 or corrected for Glacial‐Isostatic Adjustment (GIA) model predictions, both on the global and the regional scale, leading to a reconciled global rate of geocentric sea level rise of 1.61 ± 0.19mm/yr over the past century in good agreement with the most recent estimates.

Stimuli-responsive materials based on renewable biopolymers are highly attractive for developing sustainable chemical sensors. Here, two spiropyran derivatives (SP1 and SP2) were synthesized and covalently grafted onto cellulose, yielding the functional materials Cel-SP1 and Cel-SP2. Cellulose was selected as a biocompatible, biodegradable, and renewable support able to provide a stable, hydrogen-bond-rich microenvironment for chromic responses. Raman spectroscopy confirmed successful esterification, while SEM-EDS analyses revealed preserved cellulose morphology and the incorporation of nitrogen-rich spiropyran moieties. Both materials exhibited pronounced solvatochromic and pH-dependent behaviors in the solid state. Diffuse reflectance measurements revealed distinct bathochromic or hypsochromic shifts depending on solvent polarity and specific solute–matrix interactions, with DMF and DMSO producing the strongest responses. Under acidic vapors, both materials generated new absorption bands consistent with the formation of protonated merocyanine species, whereas basic vapors promoted partial or full reversion to the spiropyran form. Cel-SP1 and Cel-SP2 also displayed solvent- and pH-dependent luminescence, with Cel-SP2 showing a markedly higher sensitivity to protonation. Prototype solvent strips and acid/base vapor indicators demonstrated fast, naked-eye, reversible chromic transitions. These results highlight spiropyran-modified cellulose as an effective, renewable platform for dual solvent and acid/base vapor sensing.

A data archeology exercise was carried out on sea level observations recorded during the transit of Venus across the Sun observed in 1874 from Saint Paul Island (38°41′S, 77°31 E) in the southern Indian Ocean. Historical (1874) and recent (1994–2009) sea level observations were assembled into a consistent time series. A thorough check of the data and its precise geodetic connection to the same datum was only possible thanks to the recent installation of new technologies (GPS buoy and radar water level sensor) and leveling campaigns. The estimated rate of relative sea level change, spanning the last 135 years at Saint Paul Island, was not significantly different from zero (−0.1 ± 0.3 mm yr−1), a value which could be reconciled with estimates of global average sea level rise for the 20th century assuming the DORIS vertical velocity estimate at Amsterdam Island (100 km distant) could be applied to correct for the land motion at the tide gauge. Considering the scarcity of long‐term sea level data in the Southern Hemisphere, the exercise provides an invaluable additional observational constraint for further investigations of the spatial variability of sea level change, once vertical land rates can be determined.

The typical phytoplankton succession scenario in coastal upwelling zones is high diatom growth during upwelling and flagellate dominance during water column stratification. Within the diatom/flagellate succession there exist short-term changes in diatom communities that are caused by physical, chemical and biological processes. In this study, we used an improved 2-D kinematic box model to assess the influence of these processes on diatom dynamics in an estuarine ecosystem affected by coastal upwelling. This model enabled us to separate hydrographic from biogeochemical processes occurring in the estuary. Hydrographic variables, nutrient concentrations and phytoplankton composition were determined over a 2 wk period in the Ría de Vigo, NW Spain. Two major hydrographic phases were identified which coincided with a clear temporal and spatial separation between 2 diatom assemblages:Thalassiosiraspp./Skeletonema costatumandChaetocerosspp./Cerataulina pelagica. During upwelling, horizontal (6.6 km d–1) and vertical (11.7 m d–1) convective fluxes were high, causing a net input of NO₃⁻, HPO₄2–and SiO₄H₄. During this phase theThalassiosiraspp./S. costatumstanding stock was high (>20 μmol C l–1). Hydrographic processes, however, affected theThalassiosiraspp./S. costatumassemblage more than biogeochemical processes and this resulted in the net loss of this assemblage from the Ría and its export towards the shelf. There was a significant correlation between the biogeochemical variations in this diatom assemblage and silicate, suggesting a strong dependency ofThalassiosiraspp./S. costatumon this nutrient. By comparison, due to the higher carbon-specific net growth rate of theChaetocerosspp./C. pelagicaassemblage (0.35 d–1) during upwelling, this assemblage maintained a high biomass in the Ría. Upwelling was followed by upwelling relaxation when horizontal (1.9 km d–1) and vertical fluxes (1.8 m d–1) were reduced and nutrient levels diminished. During upwelling relaxation there was an accumulation ofChaetocerosspp./C. pelagicabiomass (>18 μmol C l–1). Biogeochemical processes provoked a loss ofThalassiosiraspp./S. costatumdue to rapid sedimentation and a net increase inChaetocerosspp./C. pelagica. It is suggested that the accumulation ofChaetocerosspp. is aided by a lower sinking rate whereas the selection ofC. pelagicais more dependent on NO₃⁻ and HPO₄2–consumption. It is concluded that upwelling events in the Ría cause the exportation ofThalassiosiraspp./S. costatumstanding stock from the Ría towards the shelf, which will ultimately benefit shelf pelagic and benthic fish communities. Upwelling relaxation events favour the retention of a high standing stock ofChaetocerosspp./C. pelagica, which is then directly available to the shellfish aquaculture of the Ría.

Nine wild Iberian provenances of Castanea sativa Mill. grouped in two gene pools, North Iberian Peninsula and Mediterranean, were evaluated for several adaptive traits in two provenance-progeny trials with the aim of evaluating the role of natural selection in shaping adaptive variation and increasing our understanding of the genetic structure of this species, as well as reporting complete information on the genetic variation among and within the studied populations. An annual growth rhythm experiment was evaluated during the first 3 years after establishment for phenology, growth, stem form and survival, and a periodic drought-stress experiment was evaluated for dry weight, growth, survival and other related drought traits in both well-watered and drought-stress treatments. The high genetic variability reported in both trials is largely due to the genetic variation among populations. The significant differences reported between quantitative genetic and neutral marker differentiation indicated the local adaptation of these populations through directional selection, mainly for phenology, growth and biomass allocation. A clinal variation among populations was determined through correlations of phenology with latitude and xerothermic index of the provenances, showing that central and southern Mediterranean populations had earlier phenology than northern populations and that drought played a relevant role in this differentiation. The significant correlation between phenological traits and the ancestry values in the Mediterranean gene pool supported the different pattern of behavior between both gene pools and also indicated the existence of two ecotypes: xeric and mesophytic ecotypes, corresponding to Mediterranean and North Iberian gene pools, respectively. The results obtained in the drought-stress experiment confirmed that, in general terms, xeric populations showed a greater adaptability to drought, with more developed root systems and higher survival than northern populations. Moreover, the genetic variability observed within populations indicated the potential response capacity of Iberian C. sativa populations to undergo fast adaptive evolution.

Background Methylotrophic (methanol-utilizing) bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including Methylobacterium extorquens , can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB), the best known polyhydroxyalkanoate (PHA). With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using M. extorquens for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications. Results Our proprietary M. extorquens ATCC 55366 was found unable to yield functionalized PHAs when fed methanol and selected unsaturated carboxylic acids as secondary substrates. However, cloning of either the phaC1 or the phaC2 gene from P. fluorescens GK13, using an inducible and regulated expression system based on cumate as inducer (the cumate switch), yielded recombinant M. extorquens strains capable of incorporating modest quantities of C-C double bonds into PHA, starting from either C6= and/or C8=. The two recombinant strains gave poor results with C11=. The strain containing the phaC2 gene was better at using C8= and at incorporating C-C double bonds into PHA. Solvent fractioning indicated that the produced polymers were PHA blends that consequently originated from independent actions of the native and the recombinant PHA synthases. Conclusions This work constitutes an example of metabolic engineering applied to the construction of a methanol-utilizing bacterium capable of producing functionalized PHAs containing C-C double bonds. In this regard, the PhaC2 synthase appeared superior to the PhaC1 synthase at utilizing C8= as source of C-C double bonds and at incorporating C-C double bonds into PHA from either C6= or C8=. The M. ex-phaC2 strain is, therefore, a promising biocatalyst for generating advanced (functionalized) PHAs for future high value applications in various fields.

abstract Methanotrophs were enriched and isolated from polluted environments in Canada and Germany. Enrichments in low copper media were designed to specifically encourage growth of soluble methane monooxygenase (sMMO) containing organisms. The 10 isolates were characterized physiologically and genetically with one type I and nine type II methanotrophs being identified. Three key genes: 16S rRNA; pmoA and mmoX, encoding for the particulate and soluble methane monooxygenases respectively, were cloned from the isolates and sequenced. Phylogenetic analysis of these sequences identified strains, which were closely related to Methylococcus capsulatus, Methylocystis sp., Methylosinus sporium and Methylosinus trichosporium. Diversity of sMMO-containing methanotrophs detected in this and previous studies was rather narrow, both genetically and physiologically, suggesting possible constraints on genetic diversity of sMMO due to essential conservation of enzyme function.

Net ecosystem production (NEP) rates of dissolved organic carbon (DOC) are estimated in a coastal upwelling system. The study site is a large coastal inlet (2.76 km3) in the northern boundary (42-43⚬N) of the eastern North Atlantic upwelling system. The two-dimensional circulation pattern in the system is governed by an offshore Ekman transport quite variable in magnitude and direction. A mass balance of the short-timescale (2-4 d) changes in measured DOC profiles is performed to obtain the NEP rates. Microbial oxidation of imported labile DOC (8% of total DOC, recycling time$\\tau <$5 d) at a maximum net rate of -37 mmol C m-2d-1occurred during a downwelling episode in the middle of the highly productive spring period. On the contrary, extensive export of labile DOC ($<$15% of total DOC,$\\tau <$7 days) produced at net rates$>$42 mmol C m-2d-1took place during an upwelling episode in July, the middle of the upwelling season. This rate represents ∼20% of the net primary production, demonstrating in the field the relative importance of horizontal offshore transport of labile DOC to the export of new production in upwelling systems. An autumn wind relaxation period results in dramatic changes in DOC standing stocks (±9 μmol C L-1) caused by a conspicuous time segregation between sustained net phytoplankton production of labile DOC (+15 mmol C m-2d-1, 11 d) and subsequent rapid bacterial degradation (-63 mmol C m-2d-1, 3 d). Net horizontal export during this period was prevented by reduced offshore Ekman transport values, indicating that net DOC production is not always synonymous with net export. Finally, during the winter period, the large wind-driven net DOC horizontal exchange rates affected mainly the DOC standing stocks of no bioreactive materials in the system, whereas bacterial oxidation rates during this period reduced to less than -0.14 mmol C m-2d-1.

Lactic acid bacteria (LAB) are Gram positive bacteria, widely distributed in nature, and industrially important as they are used in a variety of industrial food fermentations. The use of genetic engineering techniques is an effective means of enhancing the industrial applicability of LAB. However, when using genetic engineering technology, safety becomes an essential factor for the application of improved LAB to the food industry. Cloning and expression systems should be derived preferably from LAB cryptic plasmids that generally encode genes for which functions can be proposed, but no phenotypes can be observed. However, some plasmid-encoded functions have been discovered in cryptic plasmids originating from Lactobacillus, Streptococcus thermophilus, and Pediococcus spp. and can be used as selective marker systems in vector construction. This article presents information concerning LAB cryptic plasmids, and their structures, functions, and applications. A total of 134 cryptic plasmids collated are discussed.