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Climate change and water scarcity are important issues for today's power sector. To inform capacity expansion decisions, hybrid life cycle assessment is used to evaluate a reference design of a parabolic trough concentrating solar power (CSP) facility located in Daggett, CA, along four sustainability metrics: life cycle (LC) greenhouse gas (GHG) emissions, water consumption, cumulative energy demand (CED), and energy payback time (EPBT). This wet-cooled, 103 MW plant utilizes mined nitrates salts in its two-tank, thermal energy storage (TES) system. Design alternatives of dry-cooling, a thermocline TES, and synthetically derived nitrate salt are evaluated. During its LC, the reference CSP plant is estimated to emit 26 g of CO(2eq) per kWh, consume 4.7 L/kWh of water, and demand 0.40 MJ(eq)/kWh of energy, resulting in an EPBT of approximately 1 year. The dry-cooled alternative is estimated to reduce LC water consumption by 77% but increase LC GHG emissions and CED by 8%. Synthetic nitrate salts may increase LC GHG emissions by 52% compared to mined. Switching from two-tank to thermocline TES configuration reduces LC GHG emissions, most significantly for plants using synthetically derived nitrate salts. CSP can significantly reduce GHG emissions compared to fossil-fueled generation; however, dry-cooling may be required in many locations to minimize water consumption.

This article focuses on the validation of the Lumped Parameter (LP) computer codes COCOSYS and ASTEC in the field of containment phenomena during severe accidents. The release of hydrogen (H2) as an open jet from the primary circuit into the containment might cause atmospheric H2-stratifications which in turn may result in an ignitable atmospheric mixture. If this mixture is ignited, the integrity of the containment can be endangered due to the pressure and temperature rise, resulting from the combustion process. The emphasis of the paper lies on these three phenomena referring to possible successive phases of a loss of coolant accident.

Atmospheric aerosols are liquid, solid, or mixed suspensions of heterogeneous chemical composition, ranging from a few nanometers to almost 100 μm in diameter. Plants are sources and sinks of these diverse aerosols. Vegetation is influenced by aerosols through the water cycle, radiation balance, and nutrient transport, on global and regional scales, but direct interactions of aerosols with plant ecophysiology have not been considered in sufficient detail. Plant surface characteristics and aerodynamic factors control deposition. These factors may be manipulated in efforts to mitigate aerosol concentrations using urban vegetation as efficient aerosol collectors. Hygroscopic aerosols deposited on leaves generate concentrated solutions that reduce surface tension and generate thin liquid films. These films are shown to enter the stomatal pores, facilitating foliar nutrient uptake and enhancing liquid water loss that is poorly controlled by stomata. Aerosol pollution can reduce plant drought tolerance and alter nutrient balance. Anthropogenic aerosols now exceed natural aerosols, particularly in urban areas. The effects of these aerosols on plants require a focused research effort.

Ammonia exchanges between the atmosphere and terrestrial ecosystems are composed of several pathways including exchange with the soil, the litter, the plant surfaces (cuticle) and through the stomata. In this study, the fate of nitrogen in the different pools (soil and plant) was analyzed with the aim of determining the sources and sink of atmospheric ammonia after slurry application on a wheat canopy. To do this, we measured ammonia exchanges between a winter wheat canopy and the atmosphere following cattle slurry application with a trailing hose. From 12 March to 8 April in Grignon near Paris, France, the ammonia fluxes ranged from an emission peak of 54,300 NH3 ng m−2 s−1 on the day of slurry application (with a median during the first 24 h of 5990 NH3 ng m−2 s−1) to a deposition flux of −600 NH3 ng m−2 s−1 (with a median during the last period of −16 NH3 ng m−2 s−1). The ammonia compensation points were evaluated for apoplasm, foliar bulk, root bulk and litter bulk tissue, as well as for soil surface. Ammonia emission potentials defined by the ratios between the concentration in [NH4+] and [H+] for each N ecosystem pool were in the same order of magnitude for the plant decomposed in apoplastic liquid, green leaf bulk tissue and cuticle, respectively, averaging at 73, 160 and 120; in green leaf bulk tissues, the emission potential decreased gradually from 230 to 78 during the period after slurry application, while in the dead leaf bulk tissues considered as litter, the emission potential reached a maximum of 50,200 after application stabilized at around 20000. The dynamic of the emission potential for roots was similar to the ammonium concentration in the first two centimeters of the soil, with a maximum of 820 reached two days after application and a minimum of 44 reached three weeks later. The surfatm-NH3 model interpreted the emission and deposition fluxes by testing soil surface resistance. We conclude that emission of the first day application was driven by climatic conditions and ammonia concentration at the soil surface, with no surface resistance and with only soil surface emission potential. On the next three days, the ammonia emission originated from the soil surface with the growth of a dry surface layer inducing surface resistance and regulated by slurry infiltration. The following days need a more detailed description of soil surface processes and the integration of vegetation exchanges (stomatal and cuticle pathways), particularly in the last period, in order to explain the ammonia deposition.

International audience; The background for this discussion was the background document in this book entitled: “Surface/atmosphere exchange of atmospheric acids and aerosols, including the effect and model treatment of chemical interactions”

Chemical processes occurring on leaf surface and in air inside vegetation canopies play significant and sometimes dominant roles on pollutant dry deposition budgets. Yet, these processes are seldom explicitly treated in dry deposition parameterizations/models. This report briefly summarizes the current knowledge, outstanding issues, and recommendations for pollutant leaf surface exchange including ammonia (NH3), ozone (O3) and nitrogen oxides (NOx = NO + NO2), acidifying pollutants, volatile organic compounds (VOCs), and atmospheric aerosols.

In this study the influence of air humidity, light, concentration and position on the leaf blade on the uptake of the anionic fluorescent dye uranine (sodium fluoresceinate) was investigated, using isolated epidermal strips (ES) of Allium porrum and of the ornamental plant Sedum telephium. The dye was applied in aqueous solution as single droplets at a defined relative humidity (rh). The proportion that penetrated the ES was immobilised on the inner side by ion exchange membranes (IEM). Uptake patterns were examined microscopically and uptake rates were quantified fluorimetrically. The distribution of the dye on the IEM indicated that uptake was restricted to stomatal areas. Uptake of the dye increased with increasing rh and was particularly high when rh was above the deliquescence point of uranine. Pre-illumination of S. telephium leaf sections increased uptake rates by a factor of 1.5 to 36 compared with leaves kept in darkness prior to the experiments. Increasing the concentration of uranine at a constant droplet volume increased overall penetration rates but decreased uptake relative to the applied dose. This decrease was most distinctive at high rh (93%). This is attributed to the extremely slow evaporation of the droplets at high solute concentrations and high rh. With both plant species variability was considerably high, even if ES were obtained from proximate regions of the same leaf. It is concluded that stomata can be an important pathway for the uptake of foliar applied substances.

Evidence for stomatal uptake of solutes by leaves without the application of surfactants or pressure has recently been provided (Eichert et al., 1998). In the present study, experimental conditions were refined in that the water potential was held at

INTRODUCTION Recent studies for postoperative pain relief after arthroscopy by intraarticular morphine or bupivacaine showed controversial results. The aim of the study was to evaluate the analgesic effect of intraarticular morphine and ropivacaine. METHODS 135 patients were randomized into 9 groups (n=15) after standardized knee-arthroscopy. They received either 1 mg or 5 mg morphine or 150 mg ropivacaine or a combination of 5 mg morphine and 75 mg ropivacaine. Drains were opened either after 10 or 30 minutes. A control-group received isotonic saline. Pain was assesed 1 h and 4 h after surgery, at 8 pm on the day of the operation and at 8am and 4 pm the following two days by a VAS scale. Tramadol consumption as rescue medication was registred. RESULTS Ropivacaine showed the best pain relief after surgery. After 24 h the pain intensity approximated in all groups and after 48 h there was no difference. Tramadol consumption was highest in the control group and lowest in the ropivacaine group (p

Summary Stomatal conductance, which controls both the exchange of water vapour and CO 2 , is thought to be strictly determined by stomatal aperture. However, water transport processes might be modified by deposition of hygroscopic salts on the leaf surface. For this reason, simultaneous measurements of gas exchange and stomatal aperture were performed on Sambucus nigra leaves before and after treatment with sub-micrometer NaNO 3 aerosol. Aerosol treatment of the leaves led to higher transpiration, which was particularly pronounced at small apertures, leading to an enhancement of minimum leaf conductance between 45 and 90%. CO 2 -uptake of Sambucus leaves was not enhanced by aerosol treatment, and consequently water use efficiency decreased at small stomatal apertures. Artificial leaves consisting of small water reservoirs tapped with filter membranes also showed an increase in evaporation after aerosol treatment, which indicates a mainly physical explanation for the findings with Sambucus leaves. Absorption and desorption of water by salt deposits due to changing thickness of the laminar sublayer and entering turbulent elements -‘bursts’- is suggested to be a possible explanation of the results. The cyclic elementary process, condensation and evaporation of water on the leaf surface, was observed microscopically under changing boundary layer conductance at 50% relative humidity (RH). Hygroscopic particles might therefore act as intermediate short-term storage or as primary evaporation sites after liquid water transport along films of salt solution through stomatal pores. A dynamic model describes the effects of cycles of short-term storage of salts. Possible consequences for plant water relations are discussed. Wasserdampf- und CO 2 -Austausch von Blattern werden durch die stomatare Leitfahigkeit reguliert, welche bislang als eine Funktion alleine der Spaltoffnungsweite gesehen wurde. Hygroskopische Salze auf der Blattoberflache konnten diese eindeutige Beziehung aufgrund ihrer Wechselwirkung mit Wasser(dampf) beeinflussen. Aus diesem Grund wurden gleichzeitig Gasaustausch und Spaltoffnungsweiten an Blattern von Holunder ( Sambucus nigra ) gemessen. Die Ergebnisse dieser Messungen vor und nach Bespruhung der Blatter mit NaNO 3 -Aerosol wurden verglichen. Nach der Aerosolbehandlung war die Transpiration signifikant erhoht. Die relative Zunahme war bei kleinen Offnungsweiten besonders stark und die mimimale Leitfahigkeit erhohte sich um 4590%. Dagegen stieg die CO 2 -Aufnahme der Sambucus -Blatter durch die Aerosolbehandlung nicht an, wodurch sich bei kleinen Spaltoffnungsweiten eine geringere Wassernutzungseffizienz ergab. Auch fur Modellblatter (kleine mit Membranfiltern verschlossene Wassergefase) wurde nach Aerosolbehandlung ein Verdunstungsanstieg gemessen, was auf eine uberwiegend physikalische Ursache der Ergebnisse an Sambucus hindeutet. Die Ursache konnte in der wiederholten Ab- und Desorption von Wasser an den Salzablagerungen liegen und auf Veranderungen der Grenzschichtdicke und das Eindringen von Turbulenzelementen (“bursts”) in die Grenzschicht zuruckgehen. Der elementare Zyklus, Kondensation und Evaporation von Wasser auf der Blattoberflache bei sich andernder Grenzschichtleitfahigkeit, wurde bei 50% relativer Feuchte mikroskopisch beobachtet. Analog konnten hygroskopische Partikel als kurzzeitige Zwischenspeicher fungieren oder, nach dem Transport flussigen Wassers entlang von Filmen aus Salzlosung durch die Spaltoffnungen, als primare Verdunstungsorte wirken. Ein dynamisches Modell beschreibt die Wirkung wiederholter kurzzeitiger Speicherung durch das Salz. Die mogliche Bedeutung der Ergebnisse fur den pflanzlichen Wasserhaushalt wird diskutiert.

The value of the controlled impedance of various track configurations is usually obtained using algebraic equations. Most of these equations, particularly those for non‐zero track thickness, have been obtained by either theoretical approximations or curve‐fitting the results of numerical solutions of the basic electromagnetic equations. With the advent of modern PCs it is now possible to calculate the impedances directly and quickly, using numerical techniques. This has the advantage of improving the accuracy of the impedance value and increasing the range of validity. Furthermore, a wider range of configurations is now possible. The paper discusses the algebraic equations and numerical solutions in more detail.

Povidone-iodine (PVP-I) is a broad-spectrum microbicide with in vitro activity against bacteria, viruses, fungi and protozoans. A 5% solution of PVP-I proved to be highly effective in ophthalmic surgery for the prophylaxis of endophthalmitis. For the antiseptic treatment of eye infections a novel application form of PVP-I has been developed by using a PVP-I liposome complex which demonstrated an excellent antimicrobial efficacy. In this study it could be shown that the novel liposomal formulations containing 2.5 or 5% PVP-I were as active as the aqueous solution against herpes simplex virus type 1, adenovirus type 8, coxsackievirus A9 and Chlamydia trachomatis in cell culture referring to equal PVP-I concentrations. Long-term cytotoxicity experiments demonstrated a moderate cytotoxicity for both formulations with a better tolerability of the liposomal PVP-I formulation compared with the aqueous solution. There is no evidence for a genotoxic activity of these agents.

Acute otitis media (AOM) is a common infection of infants and children, accounting for one third of the illnesses requiring medical intervention in the first year of life. Although amoxicillin is recommended as first-line therapy for uncomplicated AOM, several cephalosporin and related antibiotics are available as alternative treatment. These cephalosporins, however, differ in their incidence of adverse events, which may lead to problems with compliance. In a multicenter, randomized, controlled study, the efficacy and safety of loracarbef and cefprozil, two commonly used beta-lactam antibiotics, were compared in the treatment of AOM with effusion (AOME). A total of 401 children with AOME (6 months to 12 years of age) participated in this single-masked study. Patients meeting inclusion criteria were assigned randomly to receive either loracarbef or cefprozil oral suspension 30 mg/kg per day in two divided doses for 10 days. Patients were assessed at midtherapy (days 3 to 5), post therapy (within 5 days after completion of therapy), and late post therapy (14 to 21 days after completion). Of the 401 enrolled patients, 323 were considered assessable for efficacy at the posttherapy visit. No statistically significant differences in efficacy were seen with 133 (81.1%) of the 164 loracarbef patients and 138 (86.8%) of the 159 cefprozil patients considered cured or improved clinically. At the late-posttherapy visit, 271 patients were considered assessable: 122 (91.7%) of 133 patients treated with loracarbef and 119 (86.2%) of 138 patients treated with cefprozil were cured or improved. Late-posttherapy responses combined with posttherapy relapses and failures showed cure or improvement in 74.4% and 74.8% of loracarbef and cefprozil patients, respectively. Data collected on all 401 patients were included in the safety analysis of adverse events. No differences in the safety assessment were evident except for the 22 patients in the cefprozil group and 8 patients in the loracarbef group who complained of vomiting; this difference was statistically significant. Although loracarbef and cefprozil are similar in efficacy for the treatment of AOME, loracarbef may be associated with less vomiting.

Doubly [SiMe2]-bridged metallocenes (1,2-SiMe2)2{η5-C5H2-4-R}{η5-C5H-3,5-(CHMe2)2}ZrCl2 (R = H (1a), CHMe2 (1b), SiMe3 (1c), CHMe(CMe3) (1d), (+)-menthyl (1e)), when activated by methylaluminoxane (MAO), catalyze propylene polymerization with high activities. The preparations and X-ray structures of the dilithio salt of an enantiopure, doubly silylene-bridged bis(cyclopentadienyl) ligand, Li2[(1,2-Me2Si)2{C5H2-4-(1R,2S,5R-menthyl)}{(C5H-3,5-(CHMe2)2)}]·3THF, as well as the corresponding zirconocene dichloride, [(1,2-Me2Si)2{η5-C5H2-4-(1R,2S,5R-menthyl)}{η5-C5H-3,5-(CHMe2)2}]ZrCl2 (1e), are reported. The Cs-symmetric systems 1a−c are highly regiospecific and syndiospecific (>99.5%) in neat propylene. At lower propylene concentrations, polymers with lower molecular weights and tacticity (mostly m-type stereoerrors) are obtained. The microstructures of polymers produced under differing reaction conditions are consistent with stereocontrol dominated by a site epimerization process, an inversion of configurati...

In einer vergleichenden Untersuchung wird das Trag- und Verformungsverhalten von Spannbetonbalken aus hochfestem und normalfestem Beton gegenuebergestellt. Im Gebrauchslastbereich war das Verformungsverhalten der Balken aus hochfestem Beton wegen des hoeheren Elastizitaetsmoduls sowie der groesseren Biegezug- und Verbundfestigkeit deutlich steifer, auch die zeitabhaengigen Verformungen waren geringer. Unabhaengig von der Betonfestigkeit zeigten die Balken ein duktiles Bruchverhalten. Die Bruchtragfaehigkeit wurde von der Betonfestigkeit nur wenig beeinflusst, da das Versagen erst eintrat, nachdem die Spannbewehrung die Streckgrenze deutlich ueberschritten hatte. Mit den Berechnungsansaetzen nach der "Richtlinie fuer hochfesten Beton" des Deutschen Ausschusses fuer Stahlbeton koennen auch die Bruchmomente von Spannbetonbalken zutreffend ermittelt werden. (A) Titel in Englisch: Comparative investigations of prestressed beams made of normal and high-strength concrete; Titel in Franzoesisch: Analyses comparatives de poutres precontraintes flexibles en beton normal et en beton H.R.

Abiogenic N2O production was observed on aerosols collected by a high volume sampler. Dependent on relative humidity, 0.03–0.085 nmol N2O per mg aerosol (dry weight) was formed during 48 h of incubation. From pure salts containing ammonium and nitrate, N2O was emitted at lower rates compared to airborne aerosols. This may be due to differences in the overall composition of aerosols and salt particles, differences in size and surface area, or differences in deliquescence points of airborne aerosols and salt particles.

Das Hochhaus Taunustor - Japan Center zeichnen ausgefallene Architektur und Innovationen im Tragwerkskonzept und im technischen Ausbau aus. Das 115 m hohe Gebaude mit 28 Ober- und 4 Untergeschossen wurde als Stahlbetonkonstruktion geplant und ausgefuhrt. Die vertikale Tragstruktur besteht aus einer Kerngruppe und der Lochfassade, die im Sockelbereich in Einzelstutzen aufgelost ist. Um die grostmogliche Nutzflache in den unteren Geschossen zu erzielen, wurde die Lochfassade, die gleichzeitig durch Normalkraft, Biegung und Querkraft beansprucht wird, erstmals in Deutschland aus hochfestem Beton B 105 hergestellt. Die 35 cm dicken Flachdecken, die den Raum zwischen Kern und Lochfassade uber 10,80 m stutzenfrei uberspannen, ermoglichen eine flexible Buronutzung.

A hybrid life cycle assessment (LCA) is used to evaluate four sustainability metrics over the life cycle of a power tower concentrating solar power (CSP) facility: greenhouse gas (GHG) emissions, water consumption, cumulative energy demand (CED), and energy payback time (EPBT). The reference design is for a dry-cooled, 106 MW(net) power tower facility located near Tucson, AZ that uses a mixture of mined nitrate salts as the heat transfer fluid and storage medium, a two-tank thermal energy storage system designed for six hours of full load-equivalent storage, and receives auxiliary power from the local electric grid. A thermocline-based storage system, synthetically derived salts, and natural gas auxiliary power are evaluated as design alternatives. Over its life cycle, the reference plant is estimated to have GHG emissions of 37 g CO2eq/kWh, consume 1.4 L/kWh of water and 0.49 MJ/kWh of energy, and have an EPBT of 15 months. Using synthetic salts is estimated to increase GHG emissions by 12%, CED by 7%, and water consumption by 4% compared to mined salts. Natural gas auxiliary power results in greater than 10% decreases in GHG emissions, water consumption, and CED. The thermocline design is most advantageous when coupled with the use of synthetic salts.

The structures of eleven different metallocenes substituted with either methyl and/or t-butyl groups were minimized by computer molecular modeling. Using Comparative Molecular Field Analysis (CoMFA), a computer model was generated from the minimized metallocene structures and actual polymerization performance. When the model was tested, a statistically valid correlation of the model's predicted DSC melting point with the observed DSC melting point was found. The model indicates the extent of the steric effect of these alkyl substituents and their influence on the DSC melting point.

Chemically active climate compounds are either primary compounds like methane (CH4), removed by oxidation in the atmosphere, or secondary compounds like ozone (O-3), sulfate and organic aerosols, both formed and removed in the atmosphere. Man-induced climate-chemistry interaction is a two-way process: Emissions of pollutants change the atmospheric composition contributing to climate change through the aforementioned climate components, and climate change, through changes in temperature, dynamics, the hydrological cycle, atmospheric stability, and biosphere-atmosphere interactions, affects the atmospheric composition and oxidation processes in the troposphere. Here we present progress in our understanding of processes of importance for climate-chemistry interactions, and their contributions to changes in atmospheric composition and climate forcing. A key factor is the oxidation potential involving compounds like O-3 and the hydroxyl radical (OH). Reported studies represent both current and future changes. Reported results include new estimates of radiative forcing based on extensive model studies of chemically active climate compounds like O-3, and of particles inducing both direct and indirect effects. Through EU projects like ACCENT, QUANTIFY, and the AeroCom project, extensive studies on regional and sector-wise differences in the impact on atmospheric distribution are performed. Studies have shown that land-based emissions have a different effect on climate than ship and aircraft emissions, and different measures are needed to reduce the climate impact. Several areas where climate change can affect the tropospheric oxidation process and the chemical composition are identified. This can take place through enhanced stratospheric-tropospheric exchange of ozone, more frequent periods with stable conditions favoring pollution build up over industrial areas, enhanced temperature induced biogenic emissions, methane releases from permafrost thawing, and enhanced concentration through reduced biospheric uptake. During the last 5-10 years, new observational data have been made available and used for model validation and the study of atmospheric processes. Although there are significant uncertainties in the modeling of composition changes, access to new observational data has improved modeling capability. Emission scenarios for the coming decades have a large uncertainty range, in particular with respect to regional trends, leading to a significant uncertainty range in estimated regional composition changes and climate impact.

Although mice are widely used for the study of immune consequences of hemorrhage, the changes of cardiac output (CO) and blood flow (BF) in response to trauma and hemorrhage in this species have not been well defined. To study this, nonheparinized C3H/HeN mice (n = 6 per group) underwent laparotomy (i.e., trauma induced), were bled to a mean arterial pressure of 35 mmHg, and maintained for 90 min by withdrawing more blood or returning Ringer lactate. The animals were then resuscitated with four times the volume of maximal bleedout in the form of Ringer lactate over 60 min. Sham-operated mice underwent the same procedure but were neither bled nor resuscitated. At the end of hemorrhage, 60 min postresuscitation, or corresponding time after sham operation, CO and BF were determined by radioactive microspheres. Results indicate that CO and BF decreased significantly at the end of hemorrhage. Resuscitation, however, restored CO and BF in various organs except the brain and skeletal muscle. Despite this, 9 of 16 mice died within 6 days postresuscitation, whereas none of sham mice died (n = 16 per group in this additional study). Therefore, we have developed a nonheparinized model of trauma-hemorrhage and resuscitation in mice that is associated with late mortality. Furthermore, the microsphere technique provides a reliable method for assessing CO and BF in mice. Thus it may be possible to study the correlation between cardiovascular and immunologic alterations under such conditions.

Although Ringer lactate (RL) is routinely used for resuscitation, it is not known whether the volume of RL that restores cardiac output after severe hemorrhagic shock also restores the depressed effective hepatic blood flow (EHBF). To study this, a 5-cm midline laparotomy was performed in rats (i.e., trauma induced), and the animals were then bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of maximum bleedout volume was returned in the form of RL. Animals were then resuscitated with four or five times the volume of maximum bleedout with RL. EHBF was determined during hemorrhage and at various intervals thereafter by an in vivo indocyanine green (ICG) clearance technique and corrected by the appropriate hepatic extraction ratio for ICG. Cardiac output was determined by ICG dilution, and hepatic microvascular blood flow (HMBF) was measured with laser Doppler flowmetry. In addition, hepatic blood flow was assessed by using radioactive microspheres. Results indicate that resuscitation markedly improved but did not restore the depressed EHBF after trauma and hemorrhagic shock despite the fact that cardiac output was restored. Similar changes in EHBF, HMBF, and hepatic blood flow as determined by microspheres were observed, suggesting that the in vivo ICG clearance is a reliable method to assess effective hepatic perfusion. Thus the lack of restoration of EHBF may be responsible for the subsequent hepatocellular dysfunction after trauma and severe hemorrhage.

Improved data on biosphere-atmosphere exchange are fundamental to understanding the production and fate of ammonia (NH3) in the atmosphere. The GRAMINAE Integrated Experiment combined novel measurement and modelling approaches to provide the most comprehensive analysis of the interactions to date. Major inter-comparisons of micrometeorological parameters and NH3 flux measurements using the aerodynamic gradient method and relaxed eddy accumulation (REA) were conducted. These showed close agreement, though the REA systems proved insufficiently precise to investigate vertical flux divergence. Grassland management had a large effect on fluxes: emissions increased after grass cutting (−50 to 700 ng m−2 s−1 NH3) and after N-fertilization (0 to 3800 ng m−2 s−1) compared with before the cut (−60 to 40 ng m−2 s−1). Effects of advection and air chemistry were investigated using horizontal NH3 profiles, acid gas and particle flux measurements. Inverse modelling of NH3 emission from an experimental farm agreed closely with inventory estimates, while advection errors were used to correct measured grassland fluxes. Advection effects were caused both by the farm and by emissions from the field, with an inverse dispersion-deposition model providing a reliable new approach to estimate net NH3 fluxes. Effects of aerosol chemistry on net NH3 fluxes were small, while the measurements allowed NH3-induced particle growth rates to be calculated and aerosol fluxes to be corrected. Bioassays estimated the emission potential Γ = [NH4+]/[H+] for different plant pools, with the apoplast having the smallest values (30–1000). The main within-canopy sources of NH3 emission appeared to be leaf litter and the soil surface, with Γ up to 3 million and 300 000, respectively. Cuvette and within-canopy analyses confirmed the role of leaf litter NH3 emission, which, prior to cutting, was mostly recaptured within the canopy. Measured ammonia fluxes were compared with three models: an ecosystem model (PaSim), a soil vegetation atmosphere transfer model (SURFATM-NH3) and a dynamic leaf chemistry model (DCC model). The different models each reproduced the main temporal dynamics in the flux, highlighting the importance of canopy temperature dynamics (Surfatm-NH3), interactions with ecosystem nitrogen cycling (PaSim) and the role of leaf surface chemistry (DCC model). Overall, net above-canopy fluxes were mostly determined by stomatal and cuticular uptake (before the cut), leaf litter emissions (after the cut) and fertilizer and litter emissions (after fertilization). The dynamics of ammonia emission from leaf litter are identified as a priority for future research.

In the United States, concentrating solar power (CSP) is one of the most promising renewable energy (RE) technologies for reduction of electric sector greenhouse gas (GHG) emissions and for rapid capacity expansion. It is also one of the most price-competitive RE technologies, thanks in large measure to decades of field experience and consistent improvements in design. One of the key design features that makes CSP more attractive than many other RE technologies, like solar photovoltaics and wind, is the potential for including relatively low-cost and efficient thermal energy storage (TES), which can smooth the daily fluctuation of electricity production and extend its duration into the evening peak hours or longer. Because operational environmental burdens are typically small for RE technologies, life cycle assessment (LCA) is recognized as the most appropriate analytical approach for determining their environmental impacts of these technologies, including CSP. An LCA accounts for impacts from all stages in the development, operation, and decommissioning of a CSP plant, including such upstream stages as the extraction of raw materials used in system components, manufacturing of those components, and construction of the plant. The National Renewable Energy Laboratory (NREL) is undertaking an LCA of modern CSP plants, starting with those of parabolic trough design. Our LCA follows the guidelines described in the international standard series ISO 14040-44 [1]. To support this effort, we are comparing the life-cycle environmental impacts of two TES designs: two-tank, indirect molten salt and indirect thermocline. To put the environmental burden of the TES system in perspective, one recent LCA that considered a two-tank, indirect molten salt TES system on a parabolic trough CSP plant found that the TES component can account for approximately 40% of the plant’s non-operational GHG emissions [2]. As emissions associated with plant construction, operation and decommissioning are generally small for RE technologies, this analysis focuses on estimating the emissions embodied in the production of the materials used in the TES system. A CSP plant that utilizes an indirect, molten salt, TES system transfers heat from the solar field’s heat transfer fluid (HTF) to the binary molten salts of the TES system via several heat exchangers. The “cold tank” receives the heat from the solar field HTF and conveys it to the “hot tank” via another series of heat exchangers. The hot tank stores the thermal energy for power generation later in the day. A thermocline TES system is a potentially attractive alternative because it replaces the hot and cold tanks with a thermal gradient within a single tank that significantly reduces the quantity of materials required for the same amount of thermal storage. An additional advantage is that the thermocline design can replace much of the expensive molten salt with a low-cost quartzite rock or sand filler material. This LCA is based on a detailed cost specification for a 50 MWe CSP plant with six hours of molten salt thermal storage, which utilizes an indirect, two-tank configuration [3]. This cost specification, and subsequent conversations with the author, revealed enough information to estimate weights of materials (reinforcing steel, concrete, etc.) used in all components of the specified two-tank TES system. To estimate embodied GHG emissions per kilogram of each material, two life cycle inventory (LCI) databases were consulted: EcoInvent v2.0 [4], which requires materials mass data as input, and the US Economic Input-Output LCA database [5], which requires cost data as input. IPCC default global warming potentials (GWPs) give the greenhouse potential of each gas relative to that of carbon dioxide [6]. Where certain materials specified in Kelly [3] were not available in the LCI databases, the closest available proxy for those materials was selected based on such factors as peak process temperature, and similar input materials and process technology. The thermocline system was modeled using the two-tank system design as the foundation, from which materials were subtracted or substituted based on the differences and similarities of design [7]. Table 1 summarizes the results of our evaluation. Embodied emissions of GHGs from the materials used in the 6-hour, 50 MWe two-tank system are estimated to be 17,100 MTCO2e . Analogous emissions for the thermocline system are less than half of those for the two-tank: 7890 MTCO2e . The reduction of salt inventory associated with a thermocline design thus reduces both storage cost and life cycle greenhouse gas emissions. While construction-, operation- and decommissioning-related emissions are not included in this assessment, we do not expect any differences between the two system designs to significantly affect the relative results reported here. Sensitivity analysis on choices of proxy materials for the nitrate salts and calcium silicate insulation also do not significantly affect the relative results.Copyright © 2009 by ASME

The cost-effectiveness of a photovoltaic (PV) powered heat pump water heater (HPWH) system is compared to that of a traditional solar thermal water heating system. HPWH evaporators are most often located inside the conditioned building space, resulting in a year-round cooling effect in the building. This effect is beneficial during the cooling season but detrimental during the heating season. The significance of this cooling effect was evaluated as part of the life cycle cost (LCC) analysis of the PV-powered HPWH system. Four different locations were considered: Boulder, CO; Miami, FL; Chicago, IL; and Seattle, WA. For the solar thermal analysis, both electric resistance and gas-fired auxiliary water heating scenarios were considered. Life cycle costs for the PV-HPWH system were calculated for the case of a PV system dedicated to providing electricity for the HPWH, and for the case of a previously planned residential PV system being increased in size to accommodate the HPWH. This latter case uses a lower, incremental cost of increasing the size of the PV system. The most notable results of the analysis are summarized below: • In general, the solar thermal system is more cost effective than the PV-HPWH system, even using the incremental cost of increasing the size of a planned PV system. • In locations where there are incentives that apply to PV but not solar thermal systems, as in much of Colorado, the PV-HPWH system will be more cost-effective than solar thermal. • The cooling effect of the HPWH evaporator is a net benefit in Miami, FL, but a net penalty in the other three locations. • The PV-HPWH system becomes more cost-effective than solar thermal with gas auxiliary in Miami when the price of natural gas is increased from $1 to $1.50 per therm. • Increasing the price of gas in the other locations does not make the PV-HPWH system compete against solar thermal because the cooling effect penalty also increases with the price of natural gas.

This paper examines program considerations for the design of exterior space for Alzheimer's disease patients. It is directed to planners and administrators, architects and landscape architects involved in the initial planning stages of an Alzheimer's disease facility (or nursing home) building project. The focus of the study is the Alzheimer's disease patient who is no longer able to attend to the activities of daily living (middle dementia), and therefore resides in a day care facility, a special unit, or a nursing home. This paper outlines design schemes based on cognitive and behavioral symptoms of the disease. For example, sundowning (patient agitation and hallucination in late afternoon) is a common Alzheimer's diseases symptom. In order to ameliorate sundowning, the designer needs to provide not only familiarity and comfort, but also a way to minimize shadows that could be misinterpreted as frightening spectres. The exterior space should be located on the southeast side of the building in order to ensure only a monolithic building shadow cast into the garden by the afternoon sun. For this purpose, and a number of others discussed in the paper, siting is an important consideration in this design program. Considerations of agitation, frailty, loss of short-term memory, and reduced sensory perception suggest and control all elements of the design. The study presents concepts and suggestions for creating outdoor activity and garden space for Alzheimer's disease patients. The outlined concepts may also be usefully employed in an already established facility. Creating exterior space that is safe and pleasant for Alzheimer's disease patients, as well as acceptable to adninistrators and visitors, is both a challenge and an attainable goal.

The in vitro metabolism of [ 14 C]bicifadine by hepatic microsomes and hepatocytes from mouse, rat, monkey, and human was compared using radiometric high-performance liquid chromatography and liquid chromatography/tandem mass spectrometry. Two main metabolic pathways were identified in all four species. One pathway was an NADPH-dependent pathway in which the methyl group was oxidized to form a hydroxymethyl metabolite (M2). Its formation was inhibited in human microsomes only by quinidine, a CYP2D6 inhibitor. In incubations with individual cDNA-expressed human cytochromes P450, M2 was formed only by CYP2D6 and CYP1A2, with CYP2D6 activity 6-fold greater than that of CYP1A2. M2 was oxidized further to the carboxylic acid metabolite (M3) by hepatocytes from all four species. The second major metabolic pathway was an NADPH-independent oxidation at the C2 position of the pyrrolidine ring, forming a lactam metabolite (M12). This reaction was almost completely inhibited in human hepatic microsomes and mitochondria by the monoamine oxidase (MAO)-B-specific inhibitor selegiline. Clorgyline, a specific inhibitor of MAO-A, was less effective in inhibiting M12 formation. Other metabolic pathways of variable significance among the four species included the formation of carbamoyl- O -glucuronide, hydroxymethyl lactam, and carboxyl lactam. Overall, the data indicate that the primary enzymes responsible for the primary metabolism of bicifadine in humans are MAO-B and CYP2D6.

Cooperative Rooms (COR) is an interdisciplinary research and development program of GMD in collaboration with partners. Its objective is to design, develop and investigate future workspaces by bringing together information and communication technology, architecture, design and management of buildings, and new flexible forms of individual and joint work. This paper concentrates on bridging the gap between physical and virtual work environments by the development of an innovative device, called roomComputer. The roomComputer is an embedded system and as such offers unprecedented chances to administer distributed physical work environments of people from virtual ones and vice versa.

A process sequence was designed to fabricate a fully complementary BiCMOS technology. In this technology, a merged bipolar-FET device structure and common subcollector p-n-p are used to implement a complementary emitter follower circuit, yielding a strong density advantage over conventional BiCMOS logic. The problems associated with the p-n-p subcollector formation, gate oxide protection, base formation, emitter protection and source/drain formation have been addressed. The result is a technology with a process complexity that is well-managed and has high performance. >

Sacrificial oxide growth depends on previous etch conditions of trench spacer. When etch process is not optimized, the variation in the thickness of the sacrificial oxide, through which threshold-adjust implant for PMOS transistors is performed, becomes large. By improving the etch process, the variation of sacrificial oxide thickness is reduced and the variation of PMOS threshold voltages is lessened. In this paper, we describe the improved etch condition and compare the results of 0.7 /spl mu/m PMOS threshold voltages using different etch processes.