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Silver nanodecahedra and nanoplates were successfully fabricated using a simple solution method, where silver nitrate (AgNO3) was reduced with sodium borohydride (NaBH4) at melting ice temperature. Green light-emitting diode (green LED, wavelength λG = 520 nm) was irradiated into the reaction system to control the morphology of the product. The synthetic procedure was a combination of two processes including the formation of silver seeds and subsequent photomediated crystal growth. This article also presents a mechanism study of the photomediated growth of silver nanoplates and nanodecahedra. In these processes, citrate ions were used as a morphology-controlled reagent and polyvinyl pyrrolidone as a capping agent. The growth process was evaluated by dynamic light scattering and ultraviolet/visible spectra measurements. The obtained silver nanoparticles (AgNPs) possessed various shapes, including triangular, truncated triangular, hexagonal and decahedron depending on the time duration of LED irradiation. Triangular nanoplates or decahedral nanoparticles (80–100 nm) were obtained when the silver colloid was exposed to green LED irradiation for different times (30 min—76 h). The average width and thickness of such nanoparticles were estimated to be approximately 80 nm and 20 nm, respectively. The technology uniqueness in this work is that we can change the morphology of silver from plate to decahedron via prolonging the LED illumination period from 140 min to 76 h instead of changing the light wavelength or temperature of the reaction solution. The surface-enhanced Raman scattering (SERS) experiment was carried out to measure Rhodamine 6G (R6G) concentrations plated on the silicon substrates. Silver nanodecahedra can detect the low concentration of R6G (10−8 M), while silver nanoplates can detect a higher R6G concentration of 10−6 M. Silver nanodecahedra could be used as an effective SERS substrate for ultrasensitive detection.

Background: Fluid flow in microchannels is restricted to low Reynolds number regimes and hence inducing chaotic mixing in such devices is a major challenge. Over the years, the Immersed Boundary Method (IBM) has proved its ability in handling complex fluid-structure interaction problems. Objectives: Inspired by recent patents in microchannel mixing devices, we study passive mixing effects by performing two-dimensional numerical simulations of wavy wall in channel flow using IBM. Methods: The continuity and Navier-Stokes equations governing the flow are solved by fractional step based finite volume method on a staggered Cartesian grid system. Fluid variables are described by Eulerian coordinates and solid boundary by Lagrangian coordinates. A four-point Dirac delta function is used to couple both the coordinate variables. A momentum forcing term is added to the governing equation in order to impose the no-slip boundary condition between the wavy wall and fluid interface. Results: Parametric study is carried out to analyze the fluid flow characteristics by varying amplitude and wavelength of wavy wall configurations for different Reynolds number. Conclusion: Configurations of wavy wall microchannels having a higher amplitude and lower wavelengths show optimum results for mixing applications.

Shifts in natural gas supply and demand since the early 2000s have triggered proposals for import and export terminals in coastal locations around the United States. Demand for such facilities is likely to grow with increasing rates of natural gas exports. Clatsop County, Oregon, is one such location that experienced over 10 years of debate surrounding the development of these facilities. The first liquefied natural gas (LNG) facility was proposed in this area in 2004; the final was withdrawn in 2016. While residents expressed both support and opposition early on, opposition dominated by the end. Drawing on insights from the literature on social movements, we conduct a case study of community response to LNG proposals in Clatsop County. We show how opponents were able to successfully frame the potential risks of LNG in a manner that had strong community salience, allowing them to appropriate resources and create political opportunities to advance their cause and influence local and state decisions. Engaging with this case provides an opportunity to observe the behavior and decisions of both opponents and supporters over time, and how they affected project outcomes. LNG proposals in Oregon have been among the most controversial cases of LNG development in the United States. As shale gas development continues to grow, understanding the conflicts involved with its associated infrastructure is critical to creating a more just and equitable energy system.

Background Salt pond restoration aims to recover the environmental damages that accumulated over the long history of salt production. Of the restoration strategies, phytoremediation that utilizes salt-tolerant plants and soil microorganisms to reduce the salt concentrations is believed to be environmentally-friendly. However, little is known about the change of bacterial community during salt pond restoration in the context of phytoremediation. In the present study, we used 16S metagenomics to compare seasonal changes of bacterial communities between the revegetated and barren salterns at Sicao, Taiwan. Results In both saltern types, Proteobacteria, Planctomycetes, Chloroflexi, and Bacteroidetes were predominant at the phylum level. In the revegetated salterns, the soil microbiomes displayed high species diversities and underwent a stepwise transition across seasons. In the barren salterns, the soil microbiomes fluctuated greatly, indicating that mangroves tended to stabilize the soil microorganism communities over the succession. Bacteria in the order Halanaerobiaceae and archaea in the family Halobacteriaceae that were adapted to high salinity exclusively occurred in the barren salterns. Among the 441 persistent operational taxonomic units detected in the revegetated salterns, 387 (87.5%) were present as transient species in the barren salterns. Only 32 persistent bacteria were exclusively detected in the revegetated salterns. Possibly, salt-tolerant plants provided shelters for those new colonizers. Conclusions The collective data indicate that revegetation tended to stabilize the microbiome across seasons and enriched the microbial diversity in the salterns, especially species of Planctomycetes and Acidobacteria. Electronic supplementary material The online version of this article (10.1186/s12864-019-5875-y) contains supplementary material, which is available to authorized users.

Nowadays, a number of machine learning prediction methods are being applied in the field of landslide susceptibility modeling of the large area especially in the difficult hilly terrain. In the present study, hybrid machine learning approaches of Reduced Error Pruning Trees (REPT) and different ensemble techniques were used for the construction of four novel hybrid models namely Bagging based Reduced Error Pruning Trees (BREPT), MultiBoost based Reduced Error Pruning Trees (MBREPT), Rotation Forest-based Reduced Error Pruning Trees (RFREPT), Random Subspace-based Reduced Error Pruning Trees (RSREPT) for landslide susceptibility assessment and prediction. In total, ten topographical and geo-environmental landslide conditioning factors were considered for analyzing their spatial relationship with landslide occurrences. Receiver Operating Characteristic curve, Statistical Indexes, and Root Mean Square Error methods were used to validate performance of these models. Analysis of model results indicate that the BREPT is the best model for landslide susceptibility assessment in comparison to other models.

International audience; The [Re(bpy)(CO)3Cl] catalyst pioneered by Lehn for the two-electron reduction of CO2 has constantly revealed unique facets in the mechanistic understanding of the selective transformation of CO2. A novel triazole-linked ruthenium photosensitizer and a rhenium catalyst dyad was synthesized and investigated for photo-induced charge accumulation using time-resolved absorption spectroscopy. The triazole bridging ligand promoted weak electronic communication between the two units, resulting in an anodic shift of the reduction potentials of the Re moiety. Upon excitation of the photosensitizer, the first reduction of the catalyst occurred with a fast apparent rate of >5×107 s−1. Using a double-excitation nanosecond pump-pump-probe setup to track the second electron accumulation on the catalytic unit was not conclusive as no observable absorption changes occurred upon the second excitation, suggesting a pathway for an efficient intramolecular reverse electron transfer preventing the two-electron accumulation at the catalyst under our experimental conditions. Nevertheless, under continuous irradiation and with the use of sacrificial electron donors, photocatalytic CO2 reduction assays showed good turnover numbers, hinting at the non-innocent role of byproducts in solution.

We measured the spatial distribution and composition of ozone-forming hydrocarbons, alcohols, and carbonyls in Utah&rsquo, s Uinta Basin during the winter months of 2019 and 2020. The Uinta Basin contains about 10,000 producing oil and gas wells. Snow cover and the region&rsquo, s unique topography (i.e., a large basin entirely surrounded by mountains) promote strong, multi-day temperature inversion episodes that concentrate pollution and lead to wintertime ozone production. Indeed, organic compound concentrations were about eight times higher during inversion episodes than during snow-free springtime conditions. We examined spatial associations between wintertime concentrations of organics and oil and gas sources in the region, and we found that concentrations of highly reactive alkenes were higher in areas with dense oil production than in areas with dense gas production. Total alkene+acetylene concentrations were 267 (42, 1146, lower and upper 95% confidence limits) &micro, g m&minus, 3 at locations with 340 or more producing oil wells within 10 km (i.e., 75th percentile) versus 12 (9, 23) &micro, 3 at locations with 15 or fewer oil wells (i.e., 25th percentile). Twenty-eight percent of the potential for organic compounds to produce ozone was due to alkenes in areas with dense oil production. Spatial correlations and organic compound ratios indicated that the most likely source of excess alkenes in oil-producing areas was natural gas-fueled engines, especially lean-burning (i.e., high air:fuel ratio) artificial lift engines.

Air pollution causes more damage to health and economy than previously understood, contributing to approximately one in six deaths globally. However, pollution reduction policies remain controversial even when proven effective and cost negative, partially because of misunderstanding and growing mistrust in science. We used an expert assessment to bridge these research&ndash, policy divides in the State of Utah, USA, combining quantitative estimates from 23 local researchers and specialists on the human health and economic costs of air pollution. Experts estimated that air pollution in Utah causes 2480 to 8000 premature deaths annually (90% confidence interval) and decreases the median life expectancy by 1.1 to 3.6 years. Economic costs of air pollution in Utah totaled $0.75 to $3.3 billion annually, up to 1.7% of the state&rsquo, s gross domestic product. Though these results were generally in line with available estimates from downscaled national studies, they were met with surprise in the state legislature, where there had been an almost complete absence of quantitative health and economic cost estimates. We discuss the legislative and personal responses of Utah policy makers to these results and present a framework for increasing the assimilation of data into decision making via regional expert assessment. In conclusion, combining quantitative assessments from local experts is a responsive and cost-effective tool to increase trust and information uptake during time-sensitive policy windows.

International audience; A new donor–acceptor dyad composed of a BODIPY (4,4′-difluoro-4-bora-3a,4a-diaza-s-indacene) donor and a fullerene C60 acceptor has been synthesized and characterized. This derivative has been prepared using a clickable fullerene building block that bears an alkyne moiety and a maleimide unit. The post-functionalization of the maleimide group by a BODIPY thiol leads to a BODIPY-C60 dyad, leaving the alkyne moiety for further functional arrangement. On the basis of the combination of semi-empirical and density functional theory (DFT) calculations, spectroelectrochemical experiments, and steady-state and time-resolved spectroscopies, the photophysical properties of this new BODIPY-C60 dyad were thoroughly studied. By using semi-empirical calculations, the equilibrium of three conformations of the BODIPY-C60 dyad has been deduced, and their molecular orbital structures have been analyzed using DFT calculations. Two short fluorescence lifetimes were attributed to two extended conformers displaying variable donor–acceptor distances (17.5 and 20.0 Å). Additionally, the driving force for photoinduced electron transfer from the singlet excited state of BODIPY to the C60 moiety was calculated using redox potentials determined with electrochemical studies. Spectroelectrochemical measurements were also carried out to investigate the absorption profiles of radicals in the BODIPY-C60 dyad in order to assign the transient species in pump–probe experiments. Under selective photoexcitation of the BODIPY moiety, occurrences of both energy and electron transfers were demonstrated for the dyad by femtosecond and nanosecond transient absorption spectroscopies. Photoinduced electron transfer occurs in the folded conformer, while energy transfer is observed in extended conformers.

The quantitative contribution of tropical estuaries to the atmospheric CO2 budget has large uncertainties, both spatially and seasonally. We investigated the seasonal and spatial variations of carbon biogeochemistry downstream of Ho Chi Minh City (Southern Vietnam). We sampled four sites distributed from downstream of a highly urbanised watershed through mangroves to the South China Sea coast during the dry and wet seasons. Measured partial pressure of CO2 (pCO2) ranged from 660 to 3000 μatm during the dry season, and from 740 to 5000 μatm during the wet season. High organic load, dissolved oxygen saturation down to 17%, and pCO2 up to 5000 μatm at the freshwater endmember of the estuary reflected the intense human pressure on this ecosystem. We show that releases from mangrove soils affect the water column pCO2 in this large tropical estuary (~600 m wide and 10–20 m deep). This study is among the few to report direct measurements of both water pCO2 and CO2 emissions in a Southeast Asian tropical estuary located in a highly urbanised watershed. It shows that the contribution of such estuaries may have been previously underestimated, with CO2 emissions ranging from 74 to 876 mmol m−2 day−1 at low current velocity (

Four-dimensional data assimilation (FDDA) was applied in WRF-CMAQ model sensitivity tests to study the impact of observational and analysis nudging on model performance in simulating inversion layers and O3 concentration distributions within the Uintah Basin, Utah, U.S.A. in winter 2013. Observational nudging substantially improved WRF model performance in simulating surface wind fields, correcting a 10 °C warm surface temperature bias, correcting overestimation of the planetary boundary layer height (PBLH) and correcting underestimation of inversion strengths produced by regular WRF model physics without nudging. However, the combined effects of poor performance of WRF meteorological model physical parameterization schemes in simulating low clouds, and warm and moist biases in the temperature and moisture initialization and subsequent simulation fields, likely amplified the overestimation of warm clouds during inversion days when observational nudging was applied, impacting the resulting O3 photochemical formation in the chemistry model. To reduce the impact of a moist bias in the simulations on warm cloud formation, nudging with the analysis water mixing ratio above the planetary boundary layer (PBL) was applied. However, due to poor analysis vertical temperature profiles, applying analysis nudging also increased the errors in the modeled inversion layer vertical structure compared to observational nudging. Combining both observational and analysis nudging methods resulted in unrealistically extreme stratified stability that trapped pollutants at the lowest elevations at the center of the Uintah Basin and yielded the worst WRF performance in simulating inversion layer structure among the four sensitivity tests. The results of this study illustrate the importance of carefully considering the representativeness and quality of the observational and model analysis data sets when applying nudging techniques within stable PBLs, and the need to evaluate model results on a basin-wide scale.

We study the half-filled mass-imbalanced Hubbard model with spatially alternating interactions on an optical bipartite lattice by means of the dynamical mean-field theory. The Mott transition is investigated via the spin-dependent density of states and double occupancies. The phase diagrams for the homogeneous phases at zero temperature are constructed numerically. The boundary between metallic and insulating phases at zero temperature is analytically derived within the dynamical mean field theory using the equation of motion approach as the impurity solver. We found that the metallic region is reduced with increasing interaction anisotropy or mass imbalance. Our results are closely relevant to current researches in ultracold fermion experiments and can be verified through experimental observations.

The quality of herbal drugs is usually controlled using several tests recommended in a monograph. HPTLC is the method of choice for identification in many pharmacopoeias. If combined with a suitable reference material for comparison, HPTLC can provide information beyond identification and thus may simplify quality control. This paper describes, as a proof of concept, how HPTLC can be applied to define specifications for an herbal reference material and to control the quality of an herbal drug according to these specifications. Based on multiple batches of cultivated Angelica gigas root, a specific HPTLC method for identification was optimized. This method can distinguish 27 related species. It also can detect the presence of mixtures of A. gigas with two other Angelica species traded as “Dang gui” and is suitable as well for quantitative assessment of samples in a test for minimum content of the sum of decursin and decursinol angelate. The new concept of “comprehensive HPTLC fingerprinting” is proposed: HPTLC fingerprints (images), which are used for identification, are converted into peak profiles and the intensities of selected zones are quantitatively compared to those of the corresponding zones of the reference material. Following a collaborative trial involving three laboratories in three countries, the method was applied to check the quality of further candidates for establishing an appropriate reference material. In conclusion, this case demonstrates that a single HPTLC analysis can provide information about identity, purity, and minimum content of markers of an herbal drug.

A comprehensive and largest (to the best of our knowledge) database of 791 essential oil components (EOCs) with corresponding gas chromatographic retention properties has been built. With this data set, Quantitative structure–retention relationship (QSRR) models for the prediction of the Kovats retention indices (RIs) on the non-polar DB-5 stationary phase have been built using the DRAGON molecular descriptors and the regression methods: multiple linear regression (MLR) and artificial neural networks (ANN). The obtained models demonstrate good performance, evidenced by the satisfactory statistical parameters for the best MLR (R 2 = 96.75% and $$Q_{\text{ext}}^{2}$$ = 98.0%) and ANN (R 2 = 97.18% and $$Q_{\text{ext}}^{2}$$ = 98.4%) models, respectively. In addition, the built models provide information on the factors that influence the retention of EOCs over the DB-5 stationary phase. Comparisons of the statistical parameters for the QSRR models in the present study with those reported in the literature demonstrate comparable to superior performance for the former. The obtained models constitute valuable tools for the prediction of RIs for new EOCs whose experimental data are undetermined.

Yellow phosphorus is used widely in the world for production of phosphoric acid, various phosphates, flame retardant, detergent, water treatment, metal surface treatment, etc. After the production of yellow phosphorus, a large amount of phosphorus sludge is discharged to environment, causing environment pollution. This work focused on treatment of yellow phosphorus slag (YPS) and application of it as an absorbent for chromium (VI) ion and methylene blue. The YPS was first washed with water to remove phosphoferrite (FeP) and impurities and then being milled and transferred to a float sorting system to obtain YPS particles. The characteristics of YPS particles were determined by inductively coupled plasma-mass-spectrometry (ICP-MS), energy-dispersive X-ray spectroscopy (EDX), infrared spectroscopy (IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), zeta potential, and nitrogen adsorption methods. The YPS particles were retreated with NaOH, HNO3, and EDTA solutions to evaluate the influence of these agents on metal ion and organic compound adsorption ability by YPS. The adsorption parameters of chromium (VI) ion and methylene blue (MB) by treated YPS particles were recognized by the ultraviolet-visible (UV-Vis) spectrometer. The effects of temperature, pH solution, and initial concentration of absorbed substances on the adsorption ability were investigated. The adsorption isotherms and adsorption kinetics of chromium (VI) ion and MB by YPS particles were also determined. The obtained results confirmed that the green technology used to treat the YPS2 particles is suitable to obtain an effective absorbent. The adsorption efficiency of YPS2 particles for removal of chromium (VI) ions is smaller than that for removal of MB in aqueous solutions. The adsorption isotherm of MB adsorption process is complied with the Langmuir isotherm while the adsorption kinetic fits well with the pseudo-second-order reaction model. The thermodynamic parameters of MB adsorption processed on YPS2 were calculated and discussed.

In this paper, the chromium, Cr (VI), ion adsorption ability of oyster shell samples collected from two sea regions in Vietnam (Phu Yen province and Quang Ninh province) was investigated and compared. The oyster shell samples were calcined at different temperatures and denatured by using ethylenediaminetetraacetic acid (EDTA). The Cr (VI) ion adsorption ability of the prismatic (PP) and nacreous (NP) shell layers of oysters was also evaluated. The characteristics of oyster shell samples before and after treatment were determined by using analysis methods including XRD, IR, BET, UV-Vis, and FESEM. The Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich models and fit statistic equations were used to study the adsorption isotherms of Cr (VI) ion adsorption by oyster shells. The Cr (VI) ions adsorption kinetic has been set up using four reaction models consisting of first-order, pseudo-first-order, second-order, and pseudo-second-order reaction models. Effects of experimental factors on the Cr (VI) ion adsorption process using oyster shells were also investigated and discussed in this work.

We deployed a helicopter with an infrared optical gas imaging camera to detect hydrocarbon emissions from 3,428 oil and gas facilities (including 3,225 producing oil and gas well pads) in Utah’s Uinta Basin during winter and spring 2018. We also surveyed 419 of the same well pads from the ground. Winter conditions led to poor contrast between emission plumes and the ground, leading to a detection limit for the aerial survey that was between two and six times worse than a previous summertime survey. Because the ground survey was able to use the camera’s high-sensitivity mode, the rate of detected emission plumes was much higher in the ground survey (31% of all surveyed well pads) relative to the aerial survey (0.5%), but colder air temperatures appeared to impair plume detection in the ground survey as well. The aerial survey cost less per facility visited, but the ground survey cost less per emission plume detected. Well pads with detected emissions during the ground and aerial surveys had higher oil and gas production, were younger, were more likely to be oil well pads, and had more liquid storage tanks per pad relative to the entire surveyed population. The majority of observed emission plumes were from liquid storage tanks (75.9% of all observed plumes), including emissions from pressure relief valves and thief hatches on the tank or from piping that connects to the tank. Well pads with control devices to reduce emissions from tanks (combustors or vapor recovery units) were more likely to have detected emissions. This finding does not imply that the control devices themselves were not functioning properly. Instead, gas was escaping into the atmosphere before it reached control devices. Pads with control devices tended to be newer and have higher oil and gas production, which probably explains their higher rate of detected emissions.

The heterogeneous Fenton-like catalysts based on CuFe2O4 were prepared by polymeric precursor method at several annealing temperatures. The obtained catalysts were respectively characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, point of zero charge measurement, and vibrating sample magnetometer. The Fenton-like catalytic activity was evaluated via the oxidation of methylene blue with H2O2. The results show that the CuFe2O4 phase content and the particle size increase with the annealing temperatures whereas the surface OH groups and the surface acidity decrease. The prepared powders possess typical ferromagnetic properties which allow them to be easily recovered and reused. These catalysts also present highly catalytic activities for the oxidation of methylene blue, which is principally attributed to the catalysis of the CuFe2O4 phase. When the annealing temperature increased, the catalytic performance was reduced, corresponding to the increase of par...

Besides conducive environmental factors in the tropics, pre-harvest practices significantly correlate to an increased contamination of crops by plant pathogens and related mycotoxins. Small-holder ethnic farmers are a vulnerable group in the face of these contaminations. Therefore, this study aimed to clarify the impact of traditional pre-harvest practices on the occurrence of Pusarium verticillioides and fumonisins in maize fields of two Vietnamese small-holder ethnic communities. Sampling along with a questionnaire for the inventory of pre-harvest practices was performed in the Ede (n = 18) and Kinh (n = 13) households from Vietnam between late December 2017 and early January 2019. As a result, the CP888-line fields planted by 39% of the Kinh households accumulated a higher median FB1 level of 987 +/- 843 mu g kg(-1) compared to the NK7328-line fields (0 +/- 5 mu g kg(-1)) planted by 67% of the Ede households (p-value < 0.05). Mono-cropping system (applied by 72% of the Ede and 54% of the Kinh) increased the incidence of FB1 contamination in maize fields by roughly 50% compared to mixed-cropping system. Also, the crop residues-free fields had lower the incidence of FB1 (29%, n = 17) than the fields with crop residues (71%, n = 14). Otherwise, tillage practices, pest management, and irrigation did not affect significantly FB1 contamination in their maize fields.

International audience; A unique polyoxometalate complex made up of a tetradecanuclear nickel bisphosphonate cluster capping a {SiW9} unit has been characterized. This stable compound exhibits a high hydrogen evolution reaction photocatalytic activity under visible light irradiation via a reductive quenching mechanism.

We investigate the Mott metal-insulator transition in the asymmetric Hubbard model, which may describe the ground states of fermionic atoms trapped in optical lattices. We use the dynamical mean-field theory and the equation of motion approach to calculate the density of states at the Fermi level and the double occupation for various values of the on-site interaction U and the hopping asymmetry r. The critical interaction is also obtained as a function of the hopping asymmetry. Our results are in good agreement with the ones obtained by using the dynamical mean field theory with the exact diagonalization and the quantum Monte Carlo techniques.

Methylviologen (MV2+) is perhaps the most used component as a reversible electron acceptor in photophysical studies. While MV2+ is most commonly implicated as a reversible one-electron mediator, its electrochemical properties clearly evidence two successive one-electron reduction processes. In this report, we have investigated on the light driven two-charge accumulation on MV2+ using a multicomponent system composed of the prototypical molecular photosensitizer [Ru(bpy)3]2+ and MV2+ in the presence of ascorbate as reversible electron donor. The sequential addition of two electrons on the methylviologen was tracked upon sequential excitation of the [Ru(bpy)3]2+ at optimized concentration of the electron acceptor. The charge accumulated state carries an energy of 0.9 eV above the ground state and has a lifetime of ca. 50 μs. We have reached a fairly good global yield of approximately 9% for the two-charge accumulation. This result clearly demonstrates the potential of this simple approach for applications i...

Of the blue carbon sinks, mangroves have one of the highest organic matter (OM) storage capacities in their soil due to low mineralization processes resulting from waterlogging. However, mangroves are disappearing worldwide because of demographic increases. In addition to the loss of CO2 fixation, mangrove clearing can strongly affect soil characteristics and C storage. The objectives of the present study were to quantify the evolution of soil quality, carbon stocks and carbon fluxes after mangrove clearing. Sediment cores to assess physico-chemical properties were collected and in situ CO2 fluxes were measured at the soil-air interface in a mangrove of Northern Vietnam. We compared a Kandelia candel mangrove forest with a nearby zone that had been cleared two years before the study. Significant decrease of clay content and an increase in bulk density for the upper 35cm in the cleared zone were observed. Soil organic carbon (OC) content in the upper 35cm decreased by >65% two years after clearing. The quantity and the quality of the carbon changed, with lower carbon to nitrogen ratios, indicating a more decomposed OM, a higher content of dissolved organic carbon, and a higher content of inorganic carbon (three times higher). This highlights the efficiency of mineralization processes following clearing. Due to the rapid decrease in the soil carbon content, CO2 fluxes at sediment interface were >50% lower in the cleared zone. Taking into account carbonate precipitation after OC mineralization, the mangrove soil lost ~10MgOCha-1yr-1 mostly as CO2 to the atmosphere and possibly as dissolved forms towards adjacent ecosystems. The impacts on the carbon cycle of mangrove clearing as shown by the switch from a C sink to a C source highlight the importance of maintaining these ecosystems, particularly in a context of climate change.

The ketal- or dithioketal-protected isocoumarins 15–18 gave the corresponding 1-naphthols 21–26 in their reactions with the acetoacetate (10) or pentane-2,4-dione (19) dianions and the acetone monoanion. Subjection of the dithioketal-protected ester 28 to Baker–Venkataraman reaction conditions led to the 8-deoxy tautomeric, protected forms 29/30 of the early decaketide antibiotic intermediate 2b. However, the dithioketal protecting groups could not be removed without destruction of the molecule. Consequently the silyl-protected unstable early tri- and tetracyclic decaketide biosynthesis intermediates 37a, 37b, and 38a (precursors of angucycline and anthracycline antitumor antibiotics) were prepared through silylation of 33a and 33b, to afford 34a and 34b, and subsequent treatment with acetylacetone dianion. The ultimate synthetic goal, the silyl-protected 2,3-dialkylated naphthol derivative 41, was achieved by selective elongation of the bottom chain of the bis-silyl-protected methyl ester 36 with acetylacetone dianion.

In this paper, a non-contact slippage estimation approach using sensor fusion is proposed. The sensor consists of a charge-coupled device (CCD) camera and structured light emitter. The slip margin is obtained by estimating very small displacement of the grasped object in consecutive frames sequence captured by CCD camera. In experiments, we apply our approach on a slip-margin feedback control gripper system. The three degree of freedom (DOF) gripper consisting of a CCD camera, structured light and force sensor grasps a target object. The incipient slippage occurs on the contact surface between grip fingers and grasping object when the object is pressed and slid, is estimated by proposed approach. Then, the grip force is immediately controlled by a direct feedback of the estimated slip margin. Consequently, the force is adaptively maintained in order to prevent the object from damage. The proposed approach validity is confirmed by results of experiments.

One new β-carboline alkaloid 7-methoxy-(9H-β-carbolin-1-il)-(E)-1-propenoic acid (1) together with 9-methoxycanthin-6-one (2) and 9-hydroxycanthin-6-one (3) were isolated from the hairy-root cultures of Eurycoma longifolia. The effects of these compounds on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells were investigated. Compound 1 strongly inhibited the production of NO while 2 and 3 having weak or inactive effect. Consistently, compound 1 decreased the expression of cyclooxygenase-2 and inducible nitric oxide synthase.

This empirical paper focuses on the critical success factors of international projects in Vietnam. Our regression results indicate that two factors including project conditions and partners’ capacities do not have significant impact on the project success in Vietnam. In contrast, we found only two factors including partners’ commitments and communication that have significant and positive impact on the project success. So, in an environment with many policy changes like Vietnam, if the stakeholders make strong commitments, the success likelihood of international project is higher. Also, smooth internal and external communication contributes plays an important role in the project management, stakeholder connection and decision-making process that are favorable for the project success.

We investigate two-component mass-imbalanced fermions in an optical lattice with spatially modulated interactions by using two-site dynamical mean field theory. At half-filling and zero temperature, the phase diagram of the system is analytically obtained, in which the metallic region is reduced with increasing the mass imbalance. The ground-state properties of the fermionic system are discussed from the behaviors of both the spin-dependent quasi-particle weight at the Fermi level and the double occupancy for each sublattice as functions of the local interaction strengths for various values of the mass imbalance.

Efficient methods for functionalization of readily available exo-glycals have been developed. Sequential palladium-catalysed cross-coupling of dibromo-substituted exo-glycals was first explored and allowed the formation of new disubstituted exo-glycals as single stereoisomers. Bromination of furano- and pyrano-methoxycarbonyl-exo-glycals led to a new series of monobrominated derivatives. These vinylic bromides were used in carbon-carbon bond formation through palladium-catalysed reactions, leading to a new series of previously unknown exo-glycals. Further chemical manipulation of the methoxycarbonyl functionalities and stereoselective hydrogenation of the exocyclic double bond led to C-glycosyl compounds with high stereocontrol.

Weather Research and Forecasting model inline coupled with a chemistry package PM 2.5 forecasts were assessed using fixed-site PM 2.5 concentration and specification, and mobile PM 2.5 concentration and temperature measurements from the Fairbanks winter 2008/09 field campaign. Performance differs with concentrations, varies among months and sites, and best results are achieved for PM 2.5 concentrations between 15 and 50 µg/m 3 . On average over half-a-year and all sites, 24 h-average PM 2.5 concentrations have a fractional bias and error, and a normalized mean bias and error of 22%, 67%, 13% and 71%, respectively. The skill scores derived from the mobile measurements indicate that high data density increases the representativeness of the observations and enhances the evaluation of spatial details. The model performed well for organic carbon and acceptably for sulfate, but underestimated ammonium significantly. PM 2.5 concentrations measured by two different devices at the same site indicate that measurement errors at extremely low temperatures and humidities explain up to 24% of the normalized mean error. Some discrepancies can be attributed clearly to errors in emissions, chemical boundary conditions and meteorology.