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Xylan is an important part of plant biomass and represents a renewable raw material for biorefineries. Contrary to cellulose, the structure of hemicellulose is quite complex. Therefore, the biodegradation of xylan needs the cooperation of many enzymes. For industrial production of xylanase multienzyme complexes (cocktails) and selected monocomponent xylanases, different Trichoderma reesei mutants and recombinants are used. T. reesei QM 6a (wild-type parent of best existing mutants) was selected as a starting material in the 1960s when the modern in-depth analytical methods were not yet in use. Therefore, screening of fungi genetically close to T. reesei in biodegradation of xylan may have a scientific value. Fifteen different strains from Trichoderma section Longibrachiatum have been tested for extracellular xylan-degrading enzyme production on three carbon sources (wheat straw, corn fiber, and eucalyptus wood) in shake flask cultivation. The enzyme activities were evaluated by traditional colorimetric enzyme assays and by HPLC and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Degradation of xylan was studied on four different xylan-rich model substrates. T. reesei CPK 155, Trichoderma parareesei TUB F-2535, and Trichoderma gracile TUB F-2543 isolates were equally good or better in degradation of the wheat arabinoxylan (WAX) and corn fiber alcohol insoluble solids as hydolysis substrates than the well-known T. reesei QM 6a and RUT C30 strains. Though Trichoderma saturnisporum ATCC 18903 gave relatively low volumetric enzyme activities by traditional colorimetric assays, it could release quite large amount of hydrolysis products (mono- and oligosaccharides) from WAX. Therefore, these fungi may be potential candidates for further experiments. Enzyme production on wheat straw and corn fiber carbon sources was more effective than on eucalyptus wood

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Despite the well-established finding from questionnaire studies that positive expectancies are associated with drinking behavior, there is comparatively little known about the mechanisms through which they may affect drinking behavior. Incentive motivation models suggest that alcohol itself may alter the value of the expected outcomes of drinking. The current study was designed to examine the influence of low-dose alcohol on the activation of alcohol outcome expectancy value.Forty-eight hazardous drinkers (34 men) between the ages of 21 and 35 years were recruited from advertisements in local newspapers for a social drinking study. Participants, whose most frequently consumed beverage was beer, were administered a dose of either alcoholic (8.5%) beer, based on gender and weight to reach a blood alcohol concentration of 40 mg/dl, or an equivalent volume of placebo beer. Following an absorption phase, a computerized evaluative priming task was completed in which participants made a series of judgments about the value of positive and negative outcomes following either alcohol or neutral word primes.Those who consumed alcohol made faster evaluative responses to positive relative to negative outcomes, compared with individuals who consumed the placebo beverage.These findings suggest that moderate doses of alcohol may influence the incentive value of positive relative to negative outcome expectancies. It is suggested that these processes may play a role in patterns of hazardous alcohol use.

Climate-controlled changes in eustatic sea level (ESL) are linked to transfers of water between ocean and land, thus offering a rare insight into the past hydrological cycle. In this study, we examine the timing and phase of Milankovitch-scale ESL cycles in the peak Cretaceous greenhouse, the early Turonian (-93-94 million years, Myr, ago). A high-resolution astronomical framework established for the Bohemian Cretaceous Basin (central Europe) suggests a -400-kyr pace and a distinct asymmetry of interpreted ESL cycles. The rising limbs of ESL change constitute only 20-30 % of the cycle, and are encased entirely within the falling phase of the 405-kyr eccentricity. The intervening ESL falls (<= 6 m in magnitude) are more protracted, starting within 70 kyr prior to the eccentricity minima and culminating -60 kyr after the 405-kyr eccentricity maxima. Despite similarities to the sawtooth shape of -100-kyr glacioeustatic oscillations of the Late Pleistocene, the time scales and phasing are unparalleled in the Pleistocene icehouse. A similar, 405-kyr pace is found in ice-volume variations of the early Miocene, but the timing of glacioeustatic change relative to eccentricity forcing is incompatible with the phase of greenhouse sea-level oscillations. The phasing points to major differences in the geographic location and insolation sensitivity of the key hydrological reservoirs under icehouse and greenhouse regimes. The inferred structure of greenhouse eustasy points to low- or middle-latitude water storage, likely aquifers, that charge (expand) with rising seasonality variations and discharge (contract) with declining seasonality amplitudes on the 405-kyr scale. The net volume of water transferred on these time scales is within 2.2 x 106 km3, equivalent to <= 10 % of the present-day storage in the uppermost 2 km of continental crust. Potential additive interference with steric eustasy, proportionally relevant during greenhouse regimes, could reduce the volumes required for continental storage.

Hydrogen generation from water using solar energy has grown into a promising approach for sustainable energy production. Over the last years, graphitic carbon nitrides (g-C3N4, CN), polymers based on the heptazine-group, have been widely applied as photocatalysts for H2 evolution. The poor charge separation efficiency of CN is considered the major drawback. Here, we investigated the effect of coupling CN with different types of carbon nanotubes on the charge transfer properties and the photocatalytic H2 evolution. We used carbon nanotubes (CNTs) of different wall number (single (SWCNTs), double (DWCNTs) and multi-walled (MWCNTs) CNTs) for the development of full-organic CN based composite photocatalysts. Photoactivity was drastically affected by the content but more importantly by the nature of the CNTs. The SWCNTs functionalized CN composites were the most active presenting approximately 2-5 times higher H2 evolution than the corresponding DWCNTs and MWCNTs functionalized CN under both solar and pure visible light irradiation. Photoactivity was primarily controlled by the improved electronic properties linked with the abundance and stability of photogenerated charges as evidenced by electron paramagnetic resonance spectroscopy. Transient absorption spectroscopy verified the transfer of reactive electrons from CN to CNTs. CNTs functioned as electron acceptors improving charge separation. The data suggest that charge transfer is inversely proportional to the wall number of the CNTs and that photoactivity is directly controlled by the size at the nanoscale of the CNTs used. In the CNTs/CN nanocomposites, photogenerated electrons are transferred more efficiently from CN when SWCNTs are used, providing more available electrons for H2 production.

The Vietnamese Mekong Delta (VMD) is one of the world’s most vulnerable deltas to climate change and sea level rise. Adequate understandings of future hydrological changes are crucial for effective water management and risk-proofing, however, this knowledge body is currently very limited. This study quantifies the responses of the VMD’s river flow regime to multiple stimuli, namely future upstream inflow variation, local climate change, and sea level rise. The one-dimensional hydrodynamic model MIKE 11 was used to simulate discharges and water levels across the delta. We developed four scenarios to represent changes in the upstream discharges, precipitation changes and sea level rise, covering the 2036–2065 period. We downscaled climate data and applied three bias-correction methods for five General Circulation Models (GCM), and two Representative Concentration Pathways (RCPs). The climate change projections show similar trends of increasing wet season precipitation and decreasing dry season precipitation. However, cross-scenario variations are sometimes large, depending on the individual GCMs, the RCPs and specific locations. The hydraulic simulation results indicate that, under discharge changes between −20% and +10%, combined with in-delta precipitation variations during the dry season, river discharges at the four representative stations could reduce substantially from −2.5% to −100.2%. During the wet season, the calculated river discharges show increase between 7.3% and 46.7% under four considered scenarios. Substantial changes in the VMD’s river flow regime could have potentially serious implications for water management, especially saltwater intrusion, and therefore calling for timely adaptation measures.

This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.

Stories play an exceptionally important role in how people assign value to a place. Taken together, all those stories essentially give a place an identity. The aim of placemaking is to ensure that the people using a place can appreciate that place. Placemaking approaches are focussed on strategic interventions in a place and aimed at changing the meaning and value of that place for local people, thus creating a qualitative place for enhanced storytelling. Using greenery is a common approach in place-making. Urban greenery has gone through a process of emancipation in the past 15 years. This emancipation has led to awareness that urban greenery is about more than just ecology and biodiversity, but also has social and economic consequences for a city’s fortunes. It is clear that green spaces do not stand alone: they are part of a complex urban system, and the use of green spaces in this complex system has immediate repercussions for how the city functions. With the changing role of green spaces within cities, the need to manage these spaces is emphasized. In this sense, the place-making approach, along with the storytelling approach could provide valuable insight on the planning and management of green spaces within the urban environment, with the aim to enhance quality of life by means of the social connection between people, the users of the space, and the qualitative place provided. This research illustrated that green space managers would need more social and organizational skills to manage modern urban green spaces in an attempt to create qualitative, usable spaces for citizens, spaces that are built upon stories and spaces that would further enable future stories of citizen life. The Story Behind the Place: Creating Urban Spaces That Enhance Quality of Life (PDF Download Available). Available from: https://www.researchgate.net/publication/271918395_The_Story_Behind_the_Place_Creating_Urban_Spaces_That_Enhance_Quality_of_Life [accessed Dec 21, 2015].