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The design of effective ultrafiltration/diafiltration processes for protein formulation requires the use of membranes with very high protein retention. The objective of this study was to examine the effects of specific buffers on the retention of a model protein (bovine serum albumin) during ultrafiltration. Albumin retention at pH 4.8 was significantly reduced in phosphate buffer compared with that in acetate, citrate, and histidine. This behavior was consistent with a small change in the effective albumin hydrodynamic diameter as determined by dynamic light scattering. The underlying conformational changes leading to this change in diameter were explored using circular dichroism spectroscopy and differential scanning calorimetry. These results provide important insights into the factors controlling protein retention during ultrafiltration and diafiltration. [ABSTRACT FROM AUTHOR]

During intervertebral disc (IVD) degeneration, microenvironmental challenges such as decreasing levels of glucose, oxygen, and pH play crucial roles in cell survival and matrix turnover. Antacids, such as Mg(OH)2 and CaCO3, entrapped in microcapsules are capable of neutralizing acidic microenvironments in a controlled fashion and therefore may offer the potential to improve the acidic niche of the degenerated IVD and enhance cell‐based regeneration strategies. The objectives of this work were, first, to develop and characterize antacid microcapsules and assess their neutralization capacity in an acidic microenvironment and, second, to combine antacid microcapsules with cellular microcapsules in a hybrid gel system to investigate their neutralization effect as a potential therapeutic in a disc explant model. To achieve this, we screened five different pH‐ neutralizing agents (Al(OH)3, Mg(OH)2, CaCO3, and HEPES) in terms of their pH neutralization capacities, with Mg(OH)2 or CaCO3 being carried forward for further investigation. Antacid‐alginate microcapsules were formed at different concentrations using the electrohydrodynamic spraying process and assessed in terms of size, buffering kinetics, cell compatibility, and cytotoxicity. Finally, the combination of cellular microcapsules and antacid capsules was examined in a bovine disc explant model under physiological degenerative conditions. Overall, CaCO3 was found to be superior in terms of neutralization capacities, release kinetics, and cellular response. Specifically, CaCO3 elevated the acidic pH to neutral levels and is estimated to be maintained for several weeks based on Ca2+ release. Using a disc explant model, it was demonstrated that CaCO3 microcapsules were capable of increasing the local pH within the core of a hybrid cellular gel system. This work highlights the potential of antacid microcapsules to positively alter the challenging acidic microenvironment conditions typically observed in degenerative disc disease, which may be used in conjunction with cell therapies to augment regeneration. [ABSTRACT FROM AUTHOR]

Aim: Microrefugia on alpine slopes may allow species to persist in a warming climate. How plant species richness could respond to of the effectiveness of climatic buffering, defined as the difference in climate change in a microrefugium in comparison to that of an open alpine slope as mediated by competitive priority effects, is explored. Location: Alpine habitat anywhere. Taxon: Vascular plants. Methods: A simple spatially explicit model of plant species with adaptations across a climatic gradient simulates reproduction, dispersal, and mortality through climatic change. The effectiveness of microrefugia in buffering climate change and levels of competitive priority effects are included as factors that alter demographic rates in an experimental framework. Spatial patterns of microrefugia and differences in dispersal are also simulated. Differences in mean species richness were analysed. Results: The number of species conserved, relative to an instantaneous equilibrium calculation with the same climatic change, decreases with inclusion of a period of change (transient vs. instantaneous, equilibrium change) and further with competitive priority effects. In these simulations, the number of species conserved does not simply increase with buffer effectiveness, as hypothesized, but instead is bimodal. Main Conclusions: The dip in number of species conserved in the middle range of buffer effectiveness occurs because barriers develop. These are temporal ecological traps, wherein species adapted to the middle of a climatic gradient become extinct, because their colonization of microrefugia is blocked by an extinction debt of resident species. The inertia that allows these demographic consequences is increased by competitive priorities. The highest levels of buffering and resulting inertia will not be ubiquitous but the bimodal pattern indicates that assessments of the role of microrefugia need to recognize the temporal species‐environment and species‐species interactions that will change the number of species conserved versus extinctions. [ABSTRACT FROM AUTHOR]

Forest management operations greatly influence stream habitats. Canopy clearing and subsequent canopy development during succession, site preparation, and ditching alter the light environment, and increase sediment inputs and nutrient exports from upland and riparian soils to streams. These physicochemical changes affect aquatic biofilms and metabolic rates, and in this study, we tested their individual and combined effects. We used 12 artificial streamside channels, together with a field survey of nine streams in and around clear‐cuts, to assess the effects of shading, substrate composition, and nutrient addition on biofilm biomass and composition, as well as metabolic rates. We found that biofilm biomass and gross primary production (GPP) were light limited in channels under 70% canopy shading. Nitrate additions at this shading level only marginally increased autotrophic biomass, while the rates of respiration increased 10‐fold when carbon was added. Open (unshaded) channels had three times higher rates of GPP compared with channels with 70% shading, and autotrophic biomass was twice as high, largely caused by the colonization of filamentous green algae. These changes to biofilm biomass, composition, and GPP were caused by differences in light alone, as temperature was not affected by the shading treatment. Notably, higher rates of GPP led to no positive effect on net ecosystem production. Further, fine‐grained substrates negatively affected GPP as compared with stone substrates in the experimental channels. In the surveyed streams, the negative effects of fine‐grained substrates exceeded the positive influence of light on biofilm biomass. Altogether, our results highlight the need for riparian management that protects headwaters from unwanted stressors by focusing on preventing sediment erosion and carbon transport in clear‐cuts, while providing variable shade conditions in second‐growth forests. [ABSTRACT FROM AUTHOR]

The positive effect of buffers to maintain a sui pH for microorganism growth and increase the electrolyte conductivity in microbial fuel cells (MFCs) encourages more studies on the development of new buffer solutions. The effect of types of biological buffers such as phosphate, tris, succinate, and maleate on power production in dual chamber MFC inoculated by saccharomyces cerevisiae has been examined. Electrochemical impedance spectroscopy has been used for evaluating the performance of the buffered and non‐buffered MFC systems. Considering the important impact of buffer type on the resistance of ion migration within the electrolyte and electron transport resistance of the cell components, the internal resistance of the MFC with different used buffers has been obtained and compared. According to the obtained results, the tris buffer solution showed a positive influence on the power output with a power density of 25.41% higher than phosphate. [ABSTRACT FROM AUTHOR]

Although the adverse association of loneliness with health and mortality are well documented, less is known about moderating factors of this relationship. According to the "buffering theory," it is argued that positive affect moderates the negative associations of stressors with health. The current study contributes to the literature by asking: Does positive affect also moderate the relationship between loneliness and mortality? A large population‐based sample of middle‐aged and older adults in Germany from 2008 was used (N = 4442). Mortality was monitored up to 2020, resulting in a maximum follow‐up period of observation of 12 years, in which mortality events could be observed. Loneliness was measured using an adapted German version of the De Jong Gierveld Loneliness Scale, while positive affect was measured with an adapted German version of the Positive and Negative Affect Schedule. Using Cox survival regression, it was found that loneliness significantly predicted increased mortality risk (HR = 1.20; p =.029); conversely, positive affect significantly predicted decreased mortality risk (HR = 0.63; p <.001). Furthermore, a significant interaction emerged between loneliness and positive affect in predicting mortality (HR = 0.70; p =.001): The strength of the association of loneliness with mortality decreased with increasing levels of positive affect. Positive affect attenuates the association between loneliness and mortality, supporting previous empirical research and theories on the buffering effect of positive affect. If replicated in further studies, interventions that promote positive affect might be beneficial to mitigate the negative associations of loneliness with health. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) are a cornerstone of global conservation strategies. PAs, however, are not equally effective for all threatened taxa, and it is important to understand taxa‐specific effectiveness of PAs networks.In this study, we evaluate the role of the PAs network on the protection of Asian elephants Elephas maximus and their habitats in Southeast Asia's Sundaic region. Since Asian elephants tend to prefer secondary forests or forest gaps, we predicted that PAs would not represent the species preferred habitats. We conducted the most comprehensive analysis of Asian elephant space and habitat use to date through home range estimations and step selection function analyses using over 600,000 Global Positioning System locations from 102 different elephants from Peninsular Malaysia and Borneo.Our results revealed important similarities in the habitat use of elephants in both regions, with both females and males in Peninsular Malaysia and Sabah preferring secondary forest, forest gaps and areas of regrowth and new plantations.Our results supported our prediction that PAs do not represent Asian elephants' preferred habitats, since for most of the elephants, more than half of their ranges were outside PAs and the probability of selection values for both sexes in both geographical areas were lower inside than outside the PAs.Synthesis and applications. Our analysis suggests that conservation strategies need to acknowledge that the long‐term survival of Asian elephants in the Sundaic region relies on our capacity to promote human–elephant coexistence at the boundaries of PAs. We advocate that Asian elephant conservation strategies should be based on the following three key points: (1) large PAs with core areas where elephants can find safety and potentially survive in the long term; (2) promoting connectivity among PAs using a system of wildlife corridors; and (3) effective human–elephant conflict management outside PAs. [ABSTRACT FROM AUTHOR]

Vegetated strips are in the focus of many stakeholders of agroecosystems and are part of several agri‐environmental schemes in Germany. Stakeholders have different expectations and demands on the functionality and services of vegetated strips. In our review, we focused on biodiversity and the ecosystem services pollination, conservation biocontrol, landscape aesthetics, buffer function, and biomass production and their associated functions. We assessed factors that are crucial to support service provision and reviewed trade‐offs between the ecosystem (dis)services. We identified five characteristics that are important for the provision of the assessed ecosystem services: age of vegetated strips, flower cover, size or width of the strip, management, and type of adjacent habitat. We conclude that adjusting the target of subsidies with respect to the analyzed factors for biodiversity can help to promote the multifunctionality of vegetated strips in arable farming. [ABSTRACT FROM AUTHOR]

Conservation of biodiversity in managed forest landscapes needs to be complemented with new approaches given the threat from rapid climate change. Most frameworks for adaptation of biodiversity conservation to climate change include two major strategies. The first is the resistance strategy, which focuses on actions to increase the capacity of species and communities to resist change. The second is the transformation strategy and includes actions that ease the transformation of communities to a set of species that are well adapted to the novel environmental conditions. We suggest a number of concrete actions policy makers and managers can take. Under the resistance strategy, five tools are introduced, including: identifying and protecting forest climate refugia with cold‐favored species; reducing the effects of drought by protecting the hydrological network; and actively removing competitors when they threaten cold‐favored species. Under the transformation strategy, we suggest three tools, including: enhancing conditions for forest species favored by the new climate, but currently disfavored by forest management, by planting them at suitable sites outside their main range; and increasing connectivity across the landscape to enhance the expansion of warm‐favored species to sites that have become suitable. Finally, we suggest applying a landscape perspective and simultaneously managing for both retreating and expanding species. The two different strategies (resistance and transformation) should be seen as complementary ways to maintain a rich biodiversity in future forest ecosystems. Article impact statement: The resistance and transformation strategies should be used in parallel when implementing climate adaptation for biodiversity conservation. [ABSTRACT FROM AUTHOR]

Culture‐independent survey techniques are fundamental tools when assessing plant microbiomes. These methods rely on DNA that is carefully preserved after collecting samples to achieve meaningful results. Immediately freezing samples to −80°C after collection is considered one of the most robust methods for preserving samples before DNA extraction but is often impractical. Preservation solutions can solve this problem, but commercially available products are expensive, and there is limited data comparing their efficacy with other preservation methods. In this study, we compared the impact of three methods of sample preservation on plant microbiome surveys: (1) RNAlater, a proprietary preservative, (2) a home‐made salt‐saturated dimethyl sulphoxide preservation solution (DESS), and (3) freezing at −80°C. DESS‐preserved samples, stored at room temperature for up to four weeks, did not show any significant differences to samples frozen at −80°C, while RNAlater inflated bacterial alpha diversity. Preservation treatments did not distinctively influence fungal alpha diversity. Our results demonstrate that DESS is a versatile and inexpensive preservative of DNA in plant material for diversity analyses of fungi and bacteria. [ABSTRACT FROM AUTHOR]

Electrochemical reactions in which H+ or OH− ions are produced or consumed, affect the pH near the electrode surface. Probing the pH locally is therefore highly desired to understand and model the reaction environment under operando conditions. We carried out interfacial pH measurements under mass transport control using a rotating ring‐disc electrode (RRDE) coupled with our recently developed voltammetric pH sensor. The interfacial disc pH is detected by functionalizing the gold ring with a hydroxylaminothiophenol (4‐HATP)/4‐nitrosothiophenol (4‐NSTP) redox couple. As protons only have to interact with a monolayer containing the 4‐HATP/4‐NSTP, the sensitivity and time resolution that can be achieved are superior to potentiometric sensors. We used hydrogen evolution as a model reaction and performed measurements in buffered and unbuffered electrolytes. The effects of the current density, potential, the buffer capacity of the electrolyte and rotation rate on the local pH were investigated. This work shows a reliable and sensitive method for accurately probing the reaction environment under well‐defined mass transport conditions, over a wide pH range. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a new relay selection scheme is proposed to reduce the end‐to‐end packet delivery delay for buffer‐assisted multihop decode‐and‐forward cooperative networks. The proposed method selects a relay node having more packets in the associated buffer and relay's proximity to the destination node. Mathematical expressions for the outage probability and average packet delay in Rician fading are obtained by modeling the system as a Markov chain. The proposed relay selection scheme has less packet delay as compared to the max‐link relay selection scheme with marginally higher outage probability. Thus, the proposed relay selection scheme is a good alternative to low latency wireless applications. [ABSTRACT FROM AUTHOR]

Global‐scale ocean acidification has spurred interest in the capacity of seagrass ecosystems to increase seawater pH within crucial shoreline habitats through photosynthetic activity. However, the dynamic variability of the coastal carbonate system has impeded generalization into whether seagrass aerobic metabolism ameliorates low pH on physiologically and ecologically relevant timescales. Here we present results of the most extensive study to date of pH modulation by seagrasses, spanning seven meadows (Zostera marina) and 1000 km of U.S. west coast over 6 years. Amelioration by seagrass ecosystems compared to non‐vegetated areas occurred 65% of the time (mean increase 0.07 ± 0.008 SE). Events of continuous elevation in pH within seagrass ecosystems, indicating amelioration of low pH, were longer and of greater magnitude than opposing cases of reduced pH or exacerbation. Sustained elevations in pH of >0.1, comparable to a 30% decrease in [H+], were not restricted only to daylight hours but instead persisted for up to 21 days. Maximal pH elevations occurred in spring and summer during the seagrass growth season, with a tendency for stronger effects in higher latitude meadows. These results indicate that seagrass meadows can locally alleviate low pH conditions for extended periods of time with important implications for the conservation and management of coastal ecosystems. [ABSTRACT FROM AUTHOR]

Active wildfire seasons in the western U.S. warrant the evaluation of post‐fire forest management strategies. Ground‐based salvage logging is often used to recover economic loss of burned timber. In unburned forests, ground‐based logging often follows best management practices by leaving undisturbed areas near streams called stream buffers. However, the effectiveness of these buffers has not been tested in a post‐wildfire setting. This experiment tested buffer width effectiveness with a novel field‐simulated rill experiment using sediment‐laden runoff (25 g/L) released over 40 min at evenly timed flow rates (50, 100 and 150 L/min) to measure surface runoff travel length and sediment concentration under unburned and high and low soil burn severity conditions at 2‐, 10‐ and 22‐month post‐fire. High severity areas 2‐month post‐fire had rill lengths of up to 100 m. Rill length significantly decreased over time as vegetation regrowth provided ground cover. Sediment concentration and sediment dropout rate also varied significantly by soil burn severity. Sediment concentrations were 19 g/L for the highest flow 2‐month post‐fire and reduced to 6.9–14 g/L 10‐month post‐fire due to abundant vegetation recovery. The amount of sediment dropping out of the flow consistently increased over the study period with the low burn severity rate of 1.15 g L−1 m−1 approaching the unburned rate of 1.29 g L−1 m−1 by 2‐year post‐fire. These results suggest that an often‐used standard, 15 m buffer, was sufficient to contain surface runoff and reduce sediment concentration on unburned sites, however buffers on high burn severity sites need to be eight times greater (120 m) immediately after wildfire and four times greater (60 m) 1‐year post‐fire. Low burn severity areas 1‐year post‐fire may need to be only twice the width of an unburned buffer (30 m), and 2‐year post‐fire these could return to unburned widths. [ABSTRACT FROM AUTHOR]

Advances in human technology can lead to widespread and rapid increases in interactions between wildlife and potentially disturbing stimuli. The recreational use of drones is widespread and increasing, yet laws and codes of practice which aim to manage deleterious impacts (e.g. negative interactions with wildlife) are reactionary, unscientific and inadequate.One prominent potential negative effect of drones interacting with birds is disturbance; the disruption of normal states caused by responses such as escape. We measure avian escape responses to an approaching drone (n = 561 across 22 species) to inform the development of a code of practice to manage drone‐induced disturbance. Approaches were made at a relatively high and low altitude (10 and 4 m), and at different take‐off distances, both of which are candidate prescriptions for a code of practice.Flight‐initiation distance varied between species, but not between the altitudes tested. The probability of eliciting an escape response was high, and 14.6% higher at the lower altitude (at which 88.4% of overflies resulted in an escape response). Our response rates (from terrestrial and aquatic species) are higher than those reported for different birds in other places, most of which were water or seabirds.The probability of a drone take‐off in itself eliciting a response was low (<20%) when the drone take‐off was >40 m away, and decreased further with increasing distance from birds, with no escapes occurring >120 m.Policy implications. For our sample, no drone take‐off closer than 100 m, and no flight within 100 m would eliminate the vast majority of escape responses by birds. Required separation distances between drones and wildlife may exceed those required for other human activities, such as for walkers. [ABSTRACT FROM AUTHOR]

Nowadays chemistry of 68Ga‐labelled radiopharmaceuticals is one of the drivers for Positron Emission Tomography (PET). Buffers solutions for radiolabelling play one of the important roles here. Despite HEPES buffer providing high radiochemical conversions, its use is undesirable due to high toxicity. In this article we report a simple procedure involving usage of aqueous triethanolammonium (TEA) and tris(hydroxymethyl)methyl‐ammonium (TRIS) salts of biologically active carboxylic acids in a process of gallium‐68 complexation with PSMA‐HBED‐CC. These salts provide not only high radiochemical conversions but also are already widely used in biochemistry, molecular biology, agriculture and medicine as drugs of a wide spectrum of action and growth stimulating drugs (Trekrezan™, Chlorokrezacin™). [ABSTRACT FROM AUTHOR]

Some commercial Cu (In,Ga)Se2 (CIGS) modules show large changes in current‐voltage parameters with light soaking. While such changes are not necessarily indicative of a performance problem, the associated uncertainty may be disadvantageous in a highly competitive market. Thus, it is beneficial to understand the origin of large metastabilities in order to define what processing changes might diminish metastability without impacting other desirable aspects of high‐performance devices. This study attempts to reproduce large metastabilities like those in some commercial products both through absorber and buffer processing variations in small devices. While variations of both types were found to affect metastability, only buffer variations could reproduce large metastability in high‐efficiency devices. Device modeling confirms that buffer effects alone are sufficient to explain the large metastability seen in these devices. [ABSTRACT FROM AUTHOR]

In this study, CdS chemical bath deposition is investigated to improve the performance of thin film solar cell based on Cu2ZnGeSe4/CdS heterojunction. The influence of both the bath temperature and the dipping duration on the CdS thin film properties are explored thanks to the combination of scanning electron microscopy (SEM) and Raman spectroscopy, while the photovoltaic parameters of the resulting solar cells are discussed from current–voltage (I–V) and external quantum efficiency (EQE) measurements. The highest efficiency achieved herein (without antireflection coating) is 7.6%. Although it represents 35% relative improvement compared to previous best efficiency, this champion device is still limited by interface recombination. Different strategies are finally proposed to further increase the performance of these solar cells. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical reduction of CO2 is known to be influenced by the concentration and identity of the anionic species in the electrolyte; however, a full understanding of this phenomenon has not been developed. Here, we present the results of experimental and computational studies aimed at understanding the role of electrolyte anions on the reduction of CO2 over Cu surfaces. Experimental studies were performed to show the effects of bicarbonate buffer concentration and the composition of other buffering anions on the partial currents of the major products formed by reduction of CO2 over Cu. It was demonstrated that the composition and concentration of electrolyte anions has relatively little effect on the formation of CO, HCOO−, C2H4, and CH3CH2OH, but has a significant effect on the formation of H2 and CH4. Continuum modeling was used to assess the effects of buffering anions on the pH at the electrode surface. The influence of pH on the activity of Cu for producing H2 and CH4 was also considered. Changes in the pH near the electrode surface were insufficient to explain the differences in activity and selectivity observed with changes in anion buffering capacity observed for the formation of H2 and CH4. Therefore, it is proposed that these differences are the result of the ability of buffering anions to donate hydrogen directly to the electrode surface and in competition with water. The effectiveness of buffering anions to serve as hydrogen donors is found to increase with decreasing pKa of the buffering anion. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical reduction of CO2 is known to be influenced by the concentration and identity of the anionic species in the electrolyte; however, a full understanding of this phenomenon has not been developed. Here, we present the results of experimental and computational studies aimed at understanding the role of electrolyte anions on the reduction of CO2 over Cu surfaces. Experimental studies were performed to show the effects of bicarbonate buffer concentration and the composition of other buffering anions on the partial currents of the major products formed by reduction of CO2 over Cu. It was demonstrated that the composition and concentration of electrolyte anions has relatively little effect on the formation of CO, HCOO−, C2H4, and CH3CH2OH, but has a significant effect on the formation of H2 and CH4. Continuum modeling was used to assess the effects of buffering anions on the pH at the electrode surface. The influence of pH on the activity of Cu for producing H2 and CH4 was also considered. Changes in the pH near the electrode surface were insufficient to explain the differences in activity and selectivity observed with changes in anion buffering capacity observed for the formation of H2 and CH4. Therefore, it is proposed that these differences are the result of the ability of buffering anions to donate hydrogen directly to the electrode surface and in competition with water. The effectiveness of buffering anions to serve as hydrogen donors is found to increase with decreasing pKa of the buffering anion. [ABSTRACT FROM AUTHOR]

During the production of biofuels and/or bioproducts, wood and other lignocellulosic materials are frequently exposed to buffers during enzyme treatments. Buffer pH varies according to the activity profiles of the enzyme(s) used. Time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) is an increasingly valuable analytical tool for the surface analysis of lignocellulosic solids, allowing for characterization of the lignin and polysaccharides at the surface, along with other components such as protein and inorganic salts. Despite the use of ToF‐SIMS to characterize dilute acid and alkali pretreatments of wood, the exposure of wood to buffers of intermediate pH range has not been studied as it relates to ToF‐SIMS analysis. This leads to the question: “How does soaking wood in various pH buffers impact ToF‐SIMS spectra?” Accordingly, a softwood (spruce) and hardwood (birch) were soaked in universal buffers ranging from pH 5 to 10, and then positive ion ToF‐SIMS spectra were acquired from the washed wood. Deacetylation was evident for both wood species above pH 8. Additionally, at higher pH, birch ToF‐SIMS spectra revealed a relative loss in polysaccharide peaks attributed to hemicellulose and an increase in lignin peaks. This study provides a basis for understanding the pH‐dependent alteration of wood solids in aqueous solution, which is important for understanding the controls in enzyme treatments. [ABSTRACT FROM AUTHOR]

The nature of catchment-scale sediment (dis)connectivity is the primary influence on sediment delivery to trunk streams and controls the particle size distribution of channel bed sediments. Here, we examine the distribution of major sediment buffers (floodplains, terraces, alluvial fans, trapped tributary fills), barriers (weirs), and effective catchment area (i.e. sediment contributing area) to characterize the potential for coarse sediment (dis)connectivity in 20 tributaries of Lockyer Creek, in the Lockyer Valley, SEQ. We then analyse the distribution of trunk stream sedimentary links to determine how certain tributaries or disconnecting features (buffers and barriers) influence downstream patterns of bed sediment fining along Lockyer Creek. We find that buffering increases downstream in the Lockyer Valley, and that tributary position and shape influence the space available for sediment buffering. Correspondingly, the spatial extent of sediment buffers impacts the distribution of effective catchment area, which influences the sedimentological significance of individual tributaries. Tributary sediment connectivity, the extent of overbank flows (floodwater zones), and weir locations all exert an additional influence on the distribution of sediment links along the trunk stream. These controls are related to the physiographic and climatic setting of the Lockyer Valley, and anthropogenic influences in this system. We conclude that controls on sediment connectivity and bed load sediment characteristics are highly variable between catchments, and that sediment (dis)connectivity merits equal consideration with tributary basin/channel size when determining controls on tributary-trunk stream relationships and channel sediment regime. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

One of the epitaxial issues pertaining to the growth of AlGaN/GaN HEMTs on Si is the decrease of parasitic losses that can adversely impact the RF device performances. We characterized the microwave losses in coplanar waveguides (CPWs) on GaN-based high-electron-mobility-transistors (HEMTs) and their buffer layers on Silicon substrate, up to 40 GHz. The RF losses depend not only on the crystalline quality but also on the residual tensile stress in AlN buffer, as well as its thickness. The mechanism of interfacial lossy channel induced by the piezoelectric field is discussed. Adopting a thin high-low-high temperature (HLH) AlN buffer can help to reduce the tensile stress leading to a reduction of RF losses. We suggest that a thinner p-type AlN and/or p-AlGaN-on-thin AlN near the interface can suppress the electron interfacial lossy channel, which helps the GaN-HEMT-on-HR Si to remain in a high frequency range and at high-temperature operation. [ABSTRACT FROM AUTHOR]

This review summarizes the current status of Cu(In,Ga)(S,Se)2 (CIGS) thin film solar cell technology with a focus on recent advancements and emerging concepts intended for higher efficiency and novel applications. The recent developments and trends of research in laboratories and industrial achievements communicated within the last years are reviewed, and the major developments linked to alkali post deposition treatment and composition grading in CIGS, surface passivation, buffer, and transparent contact layers are emphasized. Encouraging results have been achieved for CIGS-based tandem solar cells and for improvement in low light device performance. Challenges of technology transfer of lab's record high efficiency cells to average industrial production are obvious from the reported efficiency values. One section is dedicated to development and opportunities offered by flexible and lightweight CIGS modules. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The influence of the different side chain residues on the thermodynamic and kinetic parameters for complexation reactions of the Co2+ and Ni2+ ions has been investigated by using the isothermal titration calorimetry (ITC) technique supported by potentiometric titration data. The study was concerned with the 2 common tripodal aminocarboxylate ligands, namely, nitrilotriacetic acid and N-(2-hydroxyethyl) iminodiacetic acid. Calorimetric measurements (ITC) were run in the 2-( N-morpholino)ethanesulfonic acid hydrate (2-( N-morpholino) ethanesulfonic acid), piperazine- N, N′-bis(2-ethanesulfonic acid), and dimethylarsenic acid buffers (0.1 mol L−1, pH 6) at 298.15 K. The quantification of the metal-buffer interactions and their incorporation into the ITC data analysis enabled to obtain the pH-independent and buffer-independent thermodynamic parameters ( K, Δ G, Δ H, and Δ S) for the reactions under study. Furthermore, the kinITC method was applied to obtain kinetic information on complexation reactions from the ITC data. Correlations, based on kinetic and thermodynamic data, between the kinetics of formation of Co2+ and Ni2+ complexes and their thermodynamic stabilities are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT Ecological relationships and processes vary across species' geographic distributions, life stages and spatial, and temporal scales. Montane landscapes are characterized by low wetland densities, rugged topographies, and cold climates. Consequently, aquatic-dependent and low-vagility ectothermic species (e.g., pool-breeding amphibians) may exhibit unique ecological associations in montane landscapes. We evaluated the relative importance of breeding- and landscape-scale features associated with spotted salamander ( Ambystoma maculatum) and wood frog ( Lithobates sylvaticus) wetland occupancy in Maine's Upper Montane-Alpine Zone ecoregion, and we determined whether models performed better when the inclusive landscape-scale covariates were estimated with topography-weighted or circular buffers. We surveyed 135 potential breeding sites during May 2013-June 2014 and evaluated environmental relationships with multi-season implicit dynamics occupancy models. Breeding site occupancy by both species was influenced solely by breeding-scale habitat features. Spotted salamander occupancy probabilities increased with previous or current beaver ( Castor canadensis) presence, and models generally were better supported when the inclusive landscape-scale covariates were estimated with topography-weighted rather than circular buffers. Wood frog occupancy probabilities increased with site area and percent shallows, but neither buffer type was better supported than the other. Model rank order and support varied between buffer types, but model inferences did not. Our results suggest pool-breeding amphibian conservation in montane Maine include measures to maintain beaver populations and large wetlands with proportionally large areas of shallows ≤1-m deep. Inconsistencies between our study and previous studies substantiate the value of region-specific research for augmenting species' conservation management plans and suggest the application of out-of-region inferences may promote ineffective conservation. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The varying results reported in response to β-alanine supplementation may be related to the duration and nature of the exercise protocol employed. We investigated the effects of β-alanine supplementation on a wide range of cycling performance tests in order to produce a clear concise set of criteria for its efficacy. Fourteen trained cyclists (Age = 24.8 ± 6.7 years; VO2max = 65.4 ± 10.2 mL⋅kg⋅min-1) participated in this placebo-controlled, double-blind study. Prior to supplementation, subjects completed two (familiarization and baseline) supramaximal cycling bouts until exhaustion (120% pre-supplementation VO2max) and two 1-, 4- and 10-km cycling time trial (TT). Subjects then supplemented orally for 4 weeks with 6.4 g/d placebo or β-alanine and repeated the battery of performance tests. Blood lactate was measured pre-exercise, post-exercise and 5 min post-exercise. β-alanine supplementation elicited significant increases in time to exhaustion (TTE) (17.6 ± 11.5 s;p = 0.013, effect compared with placebo) and was likely to be beneficial to 4-km TT performance time (-7.8 ±8.1 s; 94% likelihood), despite not being statistically different (p= 0.060). Performance times in the 1- and 10-km TT were not affected by treatment. For the highly trained cyclists in the current study, β-alanine supplementation significantly extended supramaximal cycling TTE and may have provided a worthwhile improvement to 4-km TT performance. However, 1- and 10-km cycling TT performance appears to be unaffected by β-alanine supplementation. [ABSTRACT FROM AUTHOR]

Protected areas are considered vital for the conservation of biodiversity. Given their central role in many conservation strategies, it is important to know whether they adequately protect biodiversity within their boundaries; whether they are becoming more isolated from other natural areas over time; and whether they play a role in facilitating or reducing land-cover change in their surroundings. We used matching methods and national and local analyses of land-cover change to evaluate the combined effectiveness (i.e., avoided natural-cover loss), isolation (i.e., changes in adjacent areas), and spillover effects (i.e., impacts on adjacent areas) of 19 national parks in South Africa from 2000 to 2009. All parks had either similar or lower rates of natural-cover loss than matched control samples. On a national level, mean net loss of natural cover and mean net gain of cultivation cover decreased with distance from park boundary, but there was considerable variation in trends around individual parks, providing evidence for both increased isolation and buffering of protected areas. Fourteen parks had significant positive spillover and reduced natural-cover loss in their surroundings, whereas five parks experienced elevated levels of natural-cover loss. Conclusions about social-ecological spillover effects from protected areas depended heavily on the measures of land-cover change used and the scale at which the results were aggregated. Our findings emphasize the need for high-resolution data when assessing spatially explicit phenomena such as land-cover change and challenge the usefulness of large-scale (coarse grain, broad extent) studies for understanding social-ecological dynamics around protected areas. [ABSTRACT FROM AUTHOR]

A predictive model for the microbial/electrochemical base formation from wastewater was established and compared to experimental conditions within a microbial electrolysis cell. A Na2SO4/K2SO4 anolyte showed that model prediction matched experimental results. Using Shewanella oneidensis MR-1, a strong base (pH≈13) was generated using applied voltages between 0.3 and 1.1 V. Due to the use of bicarbonate, the pH value in the anolyte remained unchanged, which is required to maintain microbial activity. [ABSTRACT FROM AUTHOR]

Objective Hopelessness is a proximal risk factor of suicide. Meaning in life has been found to be a protective factor against suicidal ideation; however, the majority of studies that have explored the role of meaning in life in the context of suicidality have been conducted in nonclinical populations. The aim of this study was to investigate whether meaning in life can moderate and buffer the association between suicide risk factors and hopelessness in a clinical sample with a heightened risk of suicide. Method A total of 224 participants diagnosed with mental disorders completed self-report measures of suicide risk factors, hopelessness, and meaning in life. Results The main result from this study was that meaning in life moderated the association between suicide risk factors and hopelessness. Conclusion Meaning in life is an important variable in the prevention and treatment of people at risk of suicide. [ABSTRACT FROM AUTHOR]

In this paper, crack-free GaN films with step-graded AlGaN transition layer and AlGaN superlattice layer as buffer layers were grown on Si(111) substrate by metal-organic chemical vapor deposition(MOCVD). The combination of both buffers effectively improves the properties of GaN layer. With the optimization of the buffer structures, high quality compressively-strained GaN layers with thickness up to 3.6 µm have been obtained on Si(111) substrates [ABSTRACT FROM AUTHOR]

This cross-sectional study investigated gender and age differences on domains of stress, self-esteem and depressive symptoms, as well as the association between those domains using a sample of Norwegian adolescents (N = 1,239). The data was analysed using Pearson product moment correlation, t-tests, and hierarchical multiple regression analyses. The results showed significant differences between genders. Girls scored higher on five of seven stressor domains comprising peer pressure, home life, school attendance, school/leisure conflict and school performance as well as depression, while boys scored significantly higher on self-esteem. The hierarchical multiple regression analysis showed that higher stress from school performance and school attendance related significantly to more depressive symptoms in both genders. Additionally, stress of home life significantly related to more depressive symptoms in girls, whereas stress of peer pressure was significant in association with depressive symptoms in boys. A strong, inverse association was found between self-esteem and depression controlled for stress, especially in girls. Self-esteem was not found to be a moderator of any stressor-depression interactions. In conclusion, the results give support for the significant role of stress and self-esteem on the experience of depressive symptoms in adolescents. [ABSTRACT FROM AUTHOR]

There is strong evidence to suggest that a protein sample needs to be well folded and uniform in order to form protein crystals, and it is accepted knowledge that the formulation can have profound effects on the behaviour of the protein sample. The technique of differential scanning fluorimetry (DSF) is a very accessible method to determine protein stability as a function of the formulation chemistry and the temperature. A diverse set of 252 soluble protein samples was subjected to a standard formulation-screening protocol using DSF. Automated analysis of the DSF results suggest that in over 35% of cases buffer screening significantly increases the stability of the protein sample. Of the 28 standard formulations tested, three stood out as being statistically better than the others: these included a formulation containing the buffer citrate, long known to be `protein friendly'; bis-tris and ADA were also identified as being very useful buffers in protein formulations. [ABSTRACT FROM AUTHOR]

The ability of a recently proposed seismic isolation system, with inherent self-stopping mechanism, to mitigate or even eliminate seismic pounding of adjacent structures is investigated under severe near-fault earthquakes. The isolation system is referred to as roll-in-cage (RNC) isolator. It is a rolling-based isolator that provides in one unit the necessary functions of vertical rigid support, horizontal flexibility with enhanced stability, hysteretic energy dissipation, and resistance to minor vibration loads. In addition, the RNC isolator is distinguished by a self-stopping (buffer) mechanism to limit the bearing displacement under excitations stronger than a design earthquake or at limited seismic gaps, and a linear gravity-based self-recentering mechanism to prevent permanent bearing displacement without causing vertical fluctuation of the isolated structure. A previously developed multifeature SAP2000 model of the RNC isolator is improved in this paper to account for the inherent buffer mechanism's damping. Then, the effectiveness of the isolator's buffer mechanism in limiting peak bearing displacements is studied together with its possibly arising negative influence on the isolation efficiency. After that, the study investigates how to alleviate or even eliminate those possibly arising drawbacks, due to the developed RNC isolator's inner pounding as a result of its buffer activation, to achieve efficient seismic isolation with no direct structure-to-structure pounding, considering limited seismic gaps with adjacent structures and near-fault earthquakes. The results show that the RNC isolator could be an efficient solution for aseismic design in near-fault zones considering limited seismic gaps. Earthquake Engineering and Structural Dynamics. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The isothermal titration calorimetry (ITC) technique supported by potentiometric titration data was used to study the interaction of zinc ions with pH buffer substances, namely 2-( N-morpholino)ethanesulfonic acid (Mes), piperazine- N, N′-bis(2-ethanesulfonic acid) (Pipes), and dimethylarsenic acid (Caco). The displacement ITC titration method with nitrilotriacetic acid as a strong, competitive ligand was applied to determine conditional-independent thermodynamic parameters for the binding of Zn(II) to Mes, Pipes, and Caco. Furthermore, the relationship between the proposed coordination mode of the buffers and the binding enthalpy has been discussed. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Triclosan, an antimicrobial agent commonly used in down-the-drain consumer products, is toxic to freshwater microalgae. However, the rapid photolysis and pH-dependent dissociation of this compound may give rise to uncertainty in growth inhibition tests with freshwater microalgae, if these are not well characterized. Methods are presented to minimize these uncertainties by stabilizing pH with an organic buffering agent (Bis-Tris) and by the application of ultraviolet (UV) covers to remove UV wavelengths. Toxicity tests with these methods were in compliance with the validity criteria of the Organisation for Economic Co-operation and Development test 201, and no negative effects were seen in controls relative to the unmodified method. The methods were used for toxicity tests with triclosan at pH levels of 7.0, 8.0, and 8.5, yielding effective concentration, 10% values of 0.5 µg/L, 0.6 µg/L, and 12.1 µg/L, respectively. The observed change in toxicity with pH was proportional to the change in bioconcentration factor (BCF) as calculated using the cell model (a dynamic flux model based on the Fick-Nernst-Planck equations, in this case parameterized for an algal cell). Effect concentrations produced with the methods presented in the present study offer robust data on which to base risk assessment, and it is suggested that similar approaches be used to minimize uncertainty when other compounds that dissociate and photolyse are tested. Environ Toxicol Chem 2014;33:2551-2559. © 2014 SETAC [ABSTRACT FROM AUTHOR]

Genome size has played an important role in the evolution of plants and animals because changes in genome size seem to accompany if not facilitate evolutionary adaptation to environmental conditions. Flow cytometry (FCM) is a widespread method for determining genome size thanks to its high accuracy and speed of measurements. Nevertheless, only a few comparative studies of FCM methods exist in the field of mycology, and reviews are absent. In this study, we compared the suitability of several concentrations and RNAse A incubation times, fixatives and buffers for estimating genome size in fungi. We chose the genus Geosmithia as a model filamentous fungus. We also introduced a new standard, Aspergillus fumigatus CEA10, to determine absolute genome size. We found FCM to be an appropriate method for measuring genome size in fungi, but optimization steps showed that incorrect propidium iodide staining of nuclei can overestimate genome size due to cytoplasmic staining. We identified fixation with methanol:glacial acetic acid (3:1 v/v), 10% DMSO, 0.1% Triton-X 100, and 5 mM EDTA in combination with Tris-MgCl2 buffer as the best treatment. © 2014 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

ABSTRACT Recent national interest in golden eagle ( Aquila chrysaetos) conservation and wind energy development prompted us to investigate golden eagle home range and resource use in the Columbia Plateau Ecoregion (CPE) in Washington and Oregon. From 2004 to 2013, we deployed satellite transmitters on adult eagles ( n = 17) and monitored their movements for up to 7 years. We used the Brownian bridge movement model (BBMM) to estimate range characteristics from global position system (GPS) fixes and flight paths of 10 eagles, and modeled resource selection probability functions (RSPFs). Multi-year home ranges of resident eagles were large (99% volume contour; [ABSTRACT FROM AUTHOR]

High-efficiency blue and green light-emitting diodes (LEDs) were grown on planar Si substrates using a 5 µm thick GaN buffer by metalorganic chemical vapor deposition (MOCVD). AlN/GaN superlattices (SLs)-based interlayers were inserted twice for stress balancing and dislocation reduction. Smooth surface and low dislocation density of 1 × 109 cm-2 were achieved. The light output power (LOP) of bare 300 × 300 µm2 447 nm-LEDs and 510 nm-LEDs on Si was measured to be 2.15 mW and 0.85 mW at 20 mA, respectively. At -15 V, leakage current of as low as 3 µA was achieved for 447 nm-LEDs while higher leakage current was measured for green LEDs. After Si substrate removal, the LOP of packaged 440 nm- and 500 nm-LEDs reached 8.50 mW and 4.85 mW at 20 mA, respectively. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Vernal ponds are often treated as protected environments receiving special regulation and management. Within the landscapes where they are found, forest vegetation frequently dominates surrounding uplands and can grow to overtop and shade pond basins. Two bodies of research offer differing views of the role of forest canopy for vernal pond systems. Studies of landscape conversion suggest that removing forest overstory within uplands can cause local extinctions of amphibians by altering terrestrial habitat or hindering movement. Studies of canopy above pond basins imply an opposite relationship; encroachment of overstory vegetation can be associated with local extinctions potentially via changes in light, thermal, and food resource environments. Unresolved uncertainties about the role of forest canopy reveal significant gaps in our understanding of wetland species distributions and dynamics. Any misunderstanding of canopy influences is simultaneously important to managers because current practices emphasize promoting or conserving vegetation growth particularly within buffers immediately adjacent to ponds. We evaluated this apparent contradiction by conducting a landscape-scale, long-term experiment using 14 natural vernal ponds. Tree felling at six manipulated ponds was limited in spatial scope but was nevertheless effective in increasing water temperature. Compared with eight control ponds, manipulated ponds maintained more amphibian species during five years postmanipulation. There was little evidence that any species was negatively influenced, and the reproductive effort of species for which we estimated egg inputs maintained pretreatment population densities in manipulated compared with control ponds. Overall, our experiment shows that a carefully circumscribed reduction of overhead forest canopy can enhance the capacity of vernal ponds to support wildlife diversity and suggests a scale dependence of canopy influences on amphibians. These findings have implications for the connection between current wetland management practices and the goals of wetland stewardship and conservation of wetland-dependent species. [ABSTRACT FROM AUTHOR]

The regulation of intracellular pH ( pHi) is a fundamental aspect of cell physiology that has received little attention in studies of the phylum Cnidaria, which includes ecologically important sea anemones and reef-building corals. Like all organisms, cnidarians must maintain pH homeostasis to counterbalance reductions in pHi, which can arise because of changes in either intrinsic or extrinsic parameters. Corals and sea anemones face natural daily changes in internal fluids, where the extracellular pH can range from 8.9 during the day to 7.4 at night. Furthermore, cnidarians are likely to experience future CO2-driven declines in seawater pH, a process known as ocean acidification. Here, we carried out the first mechanistic investigation to determine how cnidarian pHi regulation responds to decreases in extracellular and intracellular pH. Using the anemone Anemonia viridis, we employed confocal live cell imaging and a pH-sensitive dye to track the dynamics of pHi after intracellular acidosis induced by acute exposure to decreases in seawater pH and NH4Cl prepulses. The investigation was conducted on cells that contained intracellular symbiotic algae ( Symbiodinium sp.) and on symbiont-free endoderm cells. Experiments using inhibitors and Na+-free seawater indicate a potential role of Na+/H+ plasma membrane exchangers (NHEs) in mediating pHi recovery following intracellular acidosis in both cell types. We also measured the buffering capacity of cells, and obtained values between 20.8 and 43.8 m m per pH unit, which are comparable to those in other invertebrates. Our findings provide the first steps towards a better understanding of acid-base regulation in these basal metazoans, for which information on cell physiology is extremely limited. [ABSTRACT FROM AUTHOR]

ABSTRACT In an effort to reduce the complexity and associated production costs of Cu(In,Ga)Se2 (CIGSe)-based solar cells, the commonly used sputtered undoped ZnO layer has been modified to eliminate the requirement for a dedicated buffer layer. After replacing the ZnO target with a mixed ZnO/ZnS target, efficient solar cells could be prepared by sputtering directly onto the as-grown CIGSe surface. This approach has now been tested with high-quality lab-scale glass/Mo/CIGSe substrates. An efficiency of 18.3% has been independently confirmed without any post-deposition annealing or light soaking. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Anthropogenic disturbance can degrade the quality of stopover sites for migratory shorebirds. We investigated the potential effects of pedestrian traffic and shellfishing on foraging shorebirds at a key stopover site at Monomoy National Wildlife Refuge (Monomoy Refuge), Massachusetts, USA. We experimentally approached 11 species of shorebirds to quantify flight-initiation distances (FID) and found that species and age affected FID. Smaller Calidris sandpipers generally allowed pedestrians to approach within 25 m before flushing, whereas larger shorebirds (black-bellied plover [ Pluvialis squatarola] and American oystercatcher [ Haematopus palliatus]) had FID over 50 m. We also found that juveniles of all species had shorter FID than adults. Based on adult FID, we developed species-specific buffer distances for 11 species that ranged from 61 m for least sandpiper ( Calidris minutilla) to 186 m for black-bellied plover. We also investigated the potential impacts of commercial and recreational shellfish harvesters, who rake for soft-shell clams ( Mya arenaria) on mudflats where shorebirds actively foraged. Microhabitats with recent shellfishing activity had a positive influence on the density of 2 species (ruddy turnstone [ Arenaria interpres], and American oystercatcher), whereas the presence of shellfishers did not appear to affect the density of other species of shorebird we monitored. We regularly detected black-bellied plovers and ruddy turnstones actively foraging in microhabitats where shellfishers had recently exposed sediment. Given the levels of shellfishing and pedestrian traffic at Monomoy Refuge, we found no evidence to suggest that current human activity has a strong negative impact on migratory shorebirds using Monomoy Refuge. However, if the amount of pedestrian traffic and shellfishing were to increase substantially, a buffer zone system might have to be implemented during peak migration periods to minimize impacts, with buffers >185 m from key foraging sites to reduce disturbance to the most sensitive species. © 2013 The Wildlife Society [ABSTRACT FROM AUTHOR]

Background Intrinsic synchronous fluctuations of the functional magnetic resonance imaging signal are indicative of the underlying 'functional connectivity' ( FC) and serve as a technique to study dynamics of the neuronal networks of the human brain. Earlier studies have characterized the functional connectivity of a distributed network of brain regions involved in swallowing, called brain swallowing network ( BSN). The potential modulatory effect of esophageal afferent signals on the BSN, however, has not been systematically studied. Methods Fourteen healthy volunteers underwent steady state functional magnetic resonance imaging across three conditions: (i) transnasal catheter placed in the esophagus without infusion; (ii) buffer solution infused at 1 mL/min; and (iii) acidic solution infused at 1 mL/min. Data were preprocessed according to the standard FC analysis pipeline. We determined the correlation coefficient values of pairs of brain regions involved in swallowing and calculated average group FC matrices across conditions. Effects of subliminal esophageal acidification and nasopharyngeal intubation were determined. Key Results Subliminal esophageal acid stimulation augmented the overall FC of the right anterior insula and specifically the FC to the left inferior parietal lobule. Conscious stimulation by nasopharyngeal intubation reduced the overall FC of the right posterior insula, particularly the FC to the right prefrontal operculum. Conclusions & Inferences The FC of BSN is amenable to modulation by sensory input. The modulatory effect of sensory pharyngoesophageal stimulation on BSN is mainly mediated through changes in the FC of the insula. The alteration induced by subliminal visceral esophageal acid stimulation is in different insular connections compared with that of conscious somatic pharyngeal stimulation. [ABSTRACT FROM AUTHOR]

We investigated the production of hydrogen peroxide ( HOOH) in illuminated seawater media containing a variety of zwitterionic buffers. Production rates varied extensively among buffers, with 4-(2-hydroxyethyl)1-piperazineethanesulfonic acid ( HEPES) highest and N-Tris(hydroxymethyl)methyl-3-aminopropanesulfonic acid ( TAPS) among the lowest. The rate of HOOH accumulation was remarkably consistent over many days, and increased linearly with buffer concentration, natural seawater concentration, and light level. Concentrations of HEPES commonly used in culture media (1-10 mM) generated enough HOOH to kill the axenic Prochlorococcus strain VOL1 during growth in enriched seawater media at lower, environmentally realistic cell concentrations and/or under high light exposure. We also demonstrated that HEPES can be used experimentally to study the biological effects of chronic exposure to sublethal levels of HOOH such as may be experienced by light-exposed microorganisms. [ABSTRACT FROM AUTHOR]

ABSTRACT The ability to grow efficient CdTe/CdS solar cells in substrate configuration would not only allow for the use of non-transparent and flexible substrates but also enable a better control of junction formation. Yet, the problems of barrier formation at the back contact as well as the formation of a p-n junction with reduced recombination losses have to be solved. In this work, CdTe/CdS solar cells in substrate configuration were developed, and the results on different combinations of back contact materials are presented. The Cu content in the electrical back contact was found to be a crucial parameter for the optimal CdCl2-treatment procedure. For Cu-free cells, two activation treatments were applied, whereas Cu-containing cells were only treated once after the CdTe deposition. A recrystallization behavior of the CdTe layer upon its activation similar to superstrate configuration was found; however, no CdTe-CdS intermixing could be observed when the layers were treated consecutively. Remarkably high VOC and fill factor of 768 mV and 68.6%, respectively, were achieved using a combination of MoO3, Te, and Cu as back contact buffer layer resulting in 11.3% conversion efficiency. With a Cu-free MoO3/Te buffer material, a VOC of 733 mV, a fill factor of 62.3%, and an efficiency of 10.0% were obtained. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A common technique for assaying lipase/esterase activity in vitro is the enzymatic cleavage of para-nitrophenyl esters, with spectrophotometric monitorization at 405-410 nm of the released p-nitrophenol ( pNP). This method has its limitations, since the extinction coefficient of pNP is strongly pH-dependent. Despite this, the method is being frequently used for investigating lipolytic activity over a pH range without any pH-related corrections, which may bring along false results. We show to what extent the results may be altered by this approach and we review alternative strategies allowing the method to become usable both in the acidic range and with varying pH. [ABSTRACT FROM AUTHOR]

We report an efficient process for the synthesis of diethyl malonate (DEM) and other malonates through the palladium-catalyzed carbonylation of chloroacetates. Excellent selectivity (96 %) and yield (94 %) were obtained without the formation of Pd black. For the first time, a weakly alkaline buffer was used to control the selectivity for DEM in the reaction and we discuss the relationship between the buffer medium and selectivity in the reaction. The combination of anisole as the solvent and a Na2HPO4/NaH2PO4 buffer was beneficial for completely restraining the phase-transfer-catalyzed substitution of DEM with ethyl chloroacetate, as well as accommodating the proposed [(PPh3)2PdI]−[Bu4N]+ intermediate, by providing a suitable environment for its stable existence. We achieved the highest efficiency in the catalytic cycle by fine-tuning the balance between the rates of oxidative addition and reductive elimination; moreover, we synthesized a recoverable heterogeneous polymer-bound Pd catalyst in 85 % yield that could be reused without an appreciable loss in activity over four cycles. [ABSTRACT FROM AUTHOR]

To meet the requirements of risk assessment legislature regarding the ecotoxicity of ionizing compounds, the present study attempts to establish easy, robust methods for testing ecotoxicity at various pH levels. An overview is given of the buffering methods found in the literature. This is supplemented by a series of experiments where toxicity and ability to stabilize pH of seven common buffering compounds was tested on Daphnia magna and Pseudokirchneriella subcapitata. We consider a buffer applicable at a given concentration if the pH drift is below 0.2 pH units, and if there are no toxic effects. Twenty-four- and 48-h acute toxicity tests with D. magna were carried on a series of organic buffers with pH monitoring. Based on the experimental results it is possible to give recommendations for buffer concentrations for use in toxicity testing with D. magna at pH levels in the range of pH 6.0-7.8 for 48 h exposure, and pH 6.0-9.5 for 24 h exposure. Forty-eight- and 72-h growth inhibition tests with P. subcapitata were carried out, and recommendations for buffer concentrations at pH 7.5 and 8.0 are made for both 48 and 72 h of exposure. Environ. Toxicol. Chem. 2012; 31: 1843-1852. © 2012 SETAC [ABSTRACT FROM AUTHOR]