Low-Temperature Effects on the Design and Performance of Composting of Explosives-Contaminated Soils

DTIC Science & Technology

1991-03-01

7 7. Aerated bins used in field composting tests on dairy manure ............................. 10 8. Typical temperature developed...during bin compostiag of dairy manure under conditions of constant airflow and optimum moisture ................. 10 9. Effect of agitation on the...temperature profile during bin composting of dairy manure

Optimising Microbial Growth with a Bench-Top Bioreactor

ERIC Educational Resources Information Center

Baker, A. M. R.; Borin, S. L.; Chooi, K. P.; Huang, S. S.; Newgas, A. J. S.; Sodagar, D.; Ziegler, C. A.; Chan, G. H. T.; Walsh, K. A. P.

2006-01-01

The effects of impeller size, agitation and aeration on the rate of yeast growth were investigated using bench-top bioreactors. This exercise, carried out over a six-month period, served as an effective demonstration of the importance of different operating parameters on cell growth and provided a means of determining the optimisation conditions…

Increased Production of Hydrogen Peroxide by Lactobacillus delbrueckii subsp. bulgaricus upon Aeration: Involvement of an NADH Oxidase in Oxidative Stress

PubMed Central

Marty-Teysset, C.; de la Torre, F.; Garel, J.-R.

2000-01-01

The growth of Lactobacillus delbrueckii subsp. bulgaricus (L. delbrueckii subsp. bulgaricus) on lactose was altered upon aerating the cultures by agitation. Aeration caused the bacteria to enter early into stationary phase, thus reducing markedly the biomass production but without modifying the maximum growth rate. The early entry into stationary phase of aerated cultures was probably related to the accumulation of hydrogen peroxide in the medium. Indeed, the concentration of hydrogen peroxide in aerated cultures was two to three times higher than in unaerated ones. Also, a similar shift from exponential to stationary phase could be induced in unaerated cultures by adding increasing concentrations of hydrogen peroxide. A significant fraction of the hydrogen peroxide produced by L. delbrueckii subsp. bulgaricus originated from the reduction of molecular oxygen by NADH catalyzed by an NADH:H2O2 oxidase. The specific activity of this NADH oxidase was the same in aerated and unaerated cultures, suggesting that the amount of this enzyme was not directly regulated by oxygen. Aeration did not change the homolactic character of lactose fermentation by L. delbrueckii subsp. bulgaricus and most of the NADH was reoxidized by lactate dehydrogenase with pyruvate. This indicated that NADH oxidase had no (or a very small) energetic role and could be involved in eliminating oxygen. PMID:10618234

Multiple electron transfer systems in oxygen reducing biocathodes revealed by different conditions of aeration/agitation.

PubMed

Rimboud, Mickaël; Bergel, Alain; Erable, Benjamin

2016-08-01

Oxygen reducing biocathodes were formed at -0.2V/SCE (+0.04V/SHE) from compost leachate. Depending on whether aeration was implemented or not, two different redox systems responsible for the electrocatalysis of oxygen reduction were evidenced. System I was observed at low potential (-0.03V/SHE) on cyclic voltammetries (CVs). It appeared during the early formation of the biocathode (few hours) and resisted the hydrodynamic conditions induced by the aeration. System II was observed at higher potential on CV (+0.46V/SHE); it required a longer lag time (up to 10days) and quiescent conditions to produce an electrochemical signal. The hydrodynamic effects produced by the forced aeration led to its extinction. From their different behaviors and examples in the literature, system I was identified as being a membrane-bound cytochrome-related molecule, while system II was identified as a soluble redox mediator excreted by the biofilm. This study highlighted the importance of controlling the local hydrodynamics to design efficient oxygen reducing biocathodes able to operate at high potential. Copyright © 2016 Elsevier B.V. All rights reserved.

Modeling of gas-liquid mass transfer in a stirred tank bioreactor agitated by a Rushton turbine or a new pitched blade impeller.

PubMed

Gelves, Ricardo; Dietrich, A; Takors, Ralf

2014-03-01

A combined computational fluid dynamics (CFD) and population balance model (PBM) approach has been applied to simulate hydrodynamics and mass transfer in a 0.18 m(3) gas-liquid stirred bioreactor agitated by (1) a Rushton turbine, and (2) a new pitched blade geometry with rotating cartridges. The operating conditions chosen were motivated by typical settings used for culturing mammalian cells. The effects of turbulence, rotating flow, bubbles breakage and coalescence were simulated using the k-ε, multiple reference frame (MRF), Sliding mesh (SM) and PBM approaches, respectively. Considering the new pitched blade geometry with rotating aeration microspargers, [Formula: see text] mass transfer was estimated to be 34 times higher than the conventional Rushton turbine set-up. Notably, the impeller power consumption was modeled to be about 50 % lower. Independent [Formula: see text] measurements applying the same operational conditions confirmed this finding. Motivated by these simulated and experimental results, the new aeration and stirring device is qualified as a very promising tool especially useful for cell culture applications which are characterized by the challenging problem of achieving relatively high mass transfer conditions while inserting only low stirrer energy.

Trehalose accumulation from corn starch by Saccharomycopsis fibuligera A11 during 2-l fermentation and trehalose purification.

PubMed

Chi, Zhe; Wang, Ji-Ming; Chi, Zhen-Ming; Ye, Fang

2010-01-01

In this study, corn starch was used as the substrate for cell growth and trehalose accumulation by Saccharomycopsis fibuligera A11. Effect of different aeration rates, agitation speeds, and concentrations of corn starch on direct conversion of corn starch to trehalose by S. fibuligera A11 were examined using a Biostat B2 2-l fermentor. We found that the optimal conditions for direct conversion of corn starch to trehalose by this yeast strain were that agitation speed was 200 rpm, aeration rate was 4.0 l/min, concentration of corn starch was 2.0% (w/v), initial pH was 5.5, fermentation temperature was 30 degrees C. Under these conditions, over 22.9 g of trehalose per 100 g of cell dry weight was accumulated in the yeast cells, cell mass was 15.2 g/l of the fermentation medium, 0.12% (w/v) of reducing sugar, and 0.21% (w/v) of total sugar were left in the fermented medium within 48 h of the fermentation. It was found that trehalose in the yeast cells could be efficiently extracted by the hot distilled water (80 degrees C). After isolation and purification, the crystal trehalose was obtained from the extract of the cells.

Analysis of the efficiency of recombinant Escherichia coli strain cultivation in a gas-vortex bioreactor.

PubMed

Savelyeva, Anna V; Nemudraya, Anna A; Podgornyi, Vladimir F; Laburkina, Nadezhda V; Ramazanov, Yuriy A; Repkov, Andrey P; Kuligina, Elena V; Richter, Vladimir A

2017-09-01

The levels of aeration and mass transfer are critical parameters required for an efficient aerobic bioprocess, and directly depend on the design features of exploited bioreactors. A novel apparatus, using gas vortex for aeration and mass transfer processes, was constructed in the Center of Vortex Technologies (Novosibirsk, Russia). In this paper, we compared the efficiency of recombinant Escherichia coli strain cultivation using novel gas-vortex technology with conventional bioprocess technologies such as shake flasks and bioreactors with mechanical stirrers. We demonstrated that the system of aeration and agitation used in gas-vortex bioreactors provides 3.6 times higher volumetric oxygen transfer coefficient in comparison with mechanical bioreactor. The use of gas-vortex bioreactor for recombinant E. coli strain cultivation allows to increase the efficiency of target protein expression at 2.2 times for BL21(DE3)/pFK2 strain and at 3.5 times for auxotrophic C600/pRT strain (in comparison with stirred bioreactor). © 2016 International Union of Biochemistry and Molecular Biology, Inc.

Comparative one-factor-at-a-time, response surface (statistical) and bench-scale bioreactor level optimization of thermoalkaline protease production from a psychrotrophic Pseudomonas putida SKG-1 isolate.

PubMed

Singh, Santosh K; Singh, Sanjay K; Tripathi, Vinayak R; Khare, Sunil K; Garg, Satyendra K

2011-12-28

Production of alkaline protease from various bacterial strains using statistical methods is customary now-a-days. The present work is first attempt for the production optimization of a solvent stable thermoalkaline protease by a psychrotrophic Pseudomonas putida isolate using conventional, response surface methods, and fermentor level optimization. The pre-screening medium amended with optimized (w/v) 1.0% glucose, 2.0% gelatin and 0.5% yeast extract, produced 278 U protease ml(-1) at 72 h incubation. Enzyme production increased to 431 Uml(-1) when Mg2+ (0.01%, w/v) was supplemented. Optimization of physical factors further enhanced protease to 514 Uml(-1) at pH 9.0, 25°C and 200 rpm within 60 h. The combined effect of conventionally optimized variables (glucose, yeast extract, MgSO4 and pH), thereafter predicted by response surface methodology yielded 617 U protease ml(-1) at glucose 1.25% (w/v), yeast extract 0.5% (w/v), MgSO4 0.01% (w/v) and pH 8.8. Bench-scale bioreactor level optimization resulted in enhanced production of 882 U protease ml(-1) at 0.8 vvm aeration and 150 rpm agitation during only 48 h incubation. The optimization of fermentation variables using conventional, statistical approaches and aeration/agitation at fermentor level resulted in ~13.5 folds increase (882 Uml(-1)) in protease production compared to un-optimized conditions (65 Uml(-1)). This is the highest level of thermoalkaline protease reported so far by any psychrotrophic bacterium.

Mass Culture of a Slime Mold, Physarum polycephalum1

PubMed Central

Brewer, E. N.; Kuraishi, S.; Garver, J. C.; Strong, F. M.

1964-01-01

The slime mold, Physarum polycephalum, was cultivated in a soluble natural medium in shake flasks and in 30-liter and 50-gal conventional baffled fermentors. Yields of 6 to 10 g (dry weight) per liter were obtained in the large-scale fermentations. Because of the slow growth of the myxomycete, particular attention had to be paid to aseptic technique. The inability of this organism to withstand the normal degree of agitation employed with most aerobic fermentations made it difficult to obtain adequate aeration. Conditions for growth of the organism on a pilot-plant scale are presented. PMID:14131366

Effect of Oxygen-Supply Rates on Growth of Escherichia coli

PubMed Central

McDaniel, L. E.; Bailey, E. G.; Zimmerli, A.

1965-01-01

The effect of oxygen-supply rates on bacterial growth was studied in commercially available unbaffled and baffled flasks with the use of Escherichia coli in a synthetic medium as a test system. The amount of growth obtained depended on the oxygen-supply rate. Based on oxygen-absorption rates (OAR) measured by the rate of sulfite oxidation, equal OAR values in different types of flasks did not give equal amounts of growth. However, growth was essentially equal at the equal sulfite-oxidation rates when these were determined in the presence of killed whole cultures. Specific growth rates were reduced only at oxygen-supply rates much lower than those at which the total amount of growth was reduced. For the physical set-up used in this work and with the biological system employed, Bellco 598 flasks and flasks fitted with Biotech stainless-steel baffles gave satisfactory results at workable broth volumes; unbaffled and Bellco 600 flasks did not. PMID:14264837

kLa of stirred tank bioreactors revisited.

PubMed

Schaepe, S; Kuprijanov, A; Sieblist, C; Jenzsch, M; Simutis, R; Lübbert, A

2013-12-01

By means of improved feedback control kLa measurements become possible at a precision and reproducibility that now allow a closer look at the influences of power input and aeration rate on the oxygen mass transfer. These measurements are performed online during running fermentations without a notable impact on the biochemical conversion processes. A closer inspection of the mass transfer during cultivations showed that at least the number of impellers influences mass transfer and mixing: On the laboratory scale, two hollow blade impellers clearly showed a larger kLa than the usually employed three impeller versions when operated at the same agitation power and aeration rate. Hollow blade impellers are preferable under most operational conditions because of their perfect gas handling capacity. Mixing time studies showed that these two impeller systems are also preferable with respect to mixing. Furthermore the widths of the baffle bars depict a significant influence on the kLa. All this clearly supports the fact that it is not only the integral power density that finally determines kLa. Copyright © 2013 Elsevier B.V. All rights reserved.

Development of an analytical microbial consortia method for enhancing performance monitoring at aerobic wastewater treatment plants.

PubMed

Razban, Behrooz; Nelson, Kristina Y; McMartin, Dena W; Cullimore, D Roy; Wall, Michelle; Wang, Dunling

2012-01-01

An analytical method to produce profiles of bacterial biomass fatty acid methyl esters (FAME) was developed employing rapid agitation followed by static incubation (RASI) using selective media of wastewater microbial communities. The results were compiled to produce a unique library for comparison and performance analysis at a Wastewater Treatment Plant (WWTP). A total of 146 samples from the aerated WWTP, comprising 73 samples of each secondary and tertiary effluent, were included analyzed. For comparison purposes, all samples were evaluated via a similarity index (SI) with secondary effluents producing an SI of 0.88 with 2.7% variation and tertiary samples producing an SI 0.86 with 5.0% variation. The results also highlighted significant differences between the fatty acid profiles of the tertiary and secondary effluents indicating considerable shifts in the bacterial community profile between these treatment phases. The WWTP performance results using this method were highly replicable and reproducible indicating that the protocol has potential as a performance-monitoring tool for aerated WWTPs. The results quickly and accurately reflect shifts in dominant bacterial communities that result when processes operations and performance change.

Mathematical model of the oxidation of ferrous iron by a biofilm of Thiobacillus ferrooxidans.

PubMed

Mesa, M M; Macías, M; Cantero, D

2002-01-01

Microbial oxidation of ferrous iron may be a viable alternative method of producing ferric sulfate, which is a reagent used for removal of H(2)S from biogas. The paper introduces a kinetic study of the biological oxidation of ferrous iron by Thiobacillus ferrooxidans immobilized on biomass support particles (BSP) composed of polyurethane foam. On the basis of the data obtained, a mathematical model for the bioreactor was subsequently developed. In the model described here, the microorganisms adhere by reversible physical adsorption to the ferric precipitates that are formed on the BSP. The model can also be considered as an expression for the erosion of microorganisms immobilized due to the agitation of the medium by aeration.

Theoretical Pressure Distribution, Apparent Mass, and Moment of Inertia of a Disk Pendulum Oscillating at Low Frequency. M.S. Thesis - George Washington Univ., Washington, D. C.

NASA Technical Reports Server (NTRS)

Dunning, R. S.

1973-01-01

Equations are developed which give the pressure profile, the forces and torques on a disk pendulum by means of point source wave theory from acoustics. The pressure, force and torque equations for an unbaffled disk are developed. These equations are then used to calculate the apparent mass and apparent inertia for the pendulum.

Oxygen mass transfer in a stirred tank bioreactor using different impeller configurations for environmental purposes

PubMed Central

2013-01-01

In this study, a miniature stirred tank bioreactor was designed for treatment of waste gas containing benzene, toluene and xylene. Oxygen mass transfer characteristics for various twin and single-impeller systems were investigated for 6 configurations in a vessel with 10 cm of inner diameter and working volume of 1.77L. Three types of impellers, namely, Rushton turbine, Pitched 4blades and Pitched 2blades impellers with downward pumping have been used. Deionized water was used as a liquid phase. With respect to other independent variables such as agitation speed, aeration rate, type of sparger, number of impellers, the relative performance of these impellers was assessed by comparing the values of (KLa) as a key parameter. Based on the experimental data, empirical correlations as a function of the operational conditions have been proposed, to study the oxygen transfer rates from air bubbles generated in the bioreactor. It was shown that twin Rushton turbine configuration demonstrates superior performance (23% to 77% enhancement in KLa) compared with other impeller compositions and that sparger type has negligible effect on oxygen mass transfer rate. Agitation speeds of 400 to 800 rpm were the most efficient speeds for oxygen mass transfer in the stirred bioreactor. PMID:23369581

Cultivation of animal cells in a reticulated vitreous carbon foam.

PubMed

Kent, B L; Mutharasan, R

1992-02-01

A reticulated vitreous carbon foam (RVCF) was used as a surface to cultivate a model anchorage-dependent animal cell line, 3T6 (mouse embryo fibroblast). This fixed-surface bioreactor provided a low-shear, chemically-inert, and reusable environment for cell growth. An external medium recirculation loop allowed aeration, nutrient monitoring, and medium replacement without disturbing the cells. Optimal flow rates for the attachment and growth phases were determined. Growth rates comparable to static (T-flask and petri dish) cultures and agitated microcarrier cultures were achieved with appropriately high medium recirculation rates. Metabolic parameters were shown to be useful indicators of cell mass, although specific glucose consumption rates were considerably higher for cultures in the RVCF reactor. Oxygen supply was shown to be the most likely limiting factor for scaleup.

Experimental and CFD-PBM Study of Oxygen Mass Transfer Coefficient in Different Impeller Configurations and Operational Conditions of a Two-Phase Partitioning Bioreactor.

PubMed

Moradkhani, Hamed; Izadkhah, Mir-Shahabeddin; Anarjan, Navideh

2017-02-01

In this work, gas dispersion in a two-phase partitioning bioreactor is analyzed by calculating volumetric oxygen mass transfer coefficient which is modeled using a commercial computational fluid dynamics (CFD), code FLUENT 6.2. Dispersed oxygen bubbles dynamics is based on standard "k-ε" Reynolds-averaged Navier-Stokes (RANS) model. This paper describes a three-dimensional CFD model coupled with population balance equations (PBE) in order to get more confirming results of experimental measurements. Values of k L a are obtained using dynamic gassing-out method. Using the CFD simulation, the volumetric mass transfer coefficient is calculated based on Higbie's penetration theory. Characteristics of mass transfer coefficient are investigated for five configurations of impeller and three different aeration flow rates. The pitched six blade type, due to the creation of downward flow direction, leads to higher dissolved oxygen (DO) concentrations, thereby, higher values of k L a compared with other impeller compositions. The magnitude of dissolved oxygen percentage in the aqueous phase has direct correlation with impeller speed and any increase of the aeration magnitude leads to faster saturation in shorter periods of time. Agitation speeds of 300 to 800 rpm are found to be the most effective rotational speeds for the mass transfer of oxygen in two-phase partitioning bioreactors (TPPB).

Effect of moisture content on fed batch composting reactor of vegetable and fruit wastes.

PubMed

Jolanun, B; Tripetchkul, S; Chiemchaisri, C; Chaiprasert, P; Towprayoon, S

2005-03-01

Vegetable and fruit wastes mixed with sawdust were composted in a laboratory scale reactor by controlling the waste feeding rate at 21 kg m(-3) day(-1) and aeration rate at 10.6 l m(-3) min(-1). The effects of initial moisture content on organic matter degradation and process performance of fed batch composting were investigated. The absolute amount of removal, removal percentage, and removal rate of dry mass obtained were substantially different among the initial moisture contents. The rapid rise of moisture content and the lowest absolute amount of removal observed were achieved in the 50% condition. The initial moisture content yielding the largest absolute amount of removal in both feeding and curing stage was 30% whereas the removal percentage and rate constant of waste decomposition were highest in the 50% condition. Examined by traditional soil physics method, the moisture content at 50-55% was suitable for satisfying the degree of free air space (65-70%) of compost during the fed batch composting. Most degradable organic matter was mainly consumed in the feeding stage as indicated by a higher removal rate of dry mass in all cases. It is recommended that the initial moisture content of 30% and mode of aeration and agitation should be adopted for achieving practical fed batch composting of vegetable and fruit wastes. The study also demonstrated that the composting kinetics of vegetable and fruit wastes mixed with sawdust can be described by a first order model.

Bioreactor engineering using disposable technology for enhanced production of hCTLA4Ig in transgenic rice cell cultures.

PubMed

Kwon, Jun-Young; Yang, Yong-Suk; Cheon, Su-Hwan; Nam, Hyung-Jin; Jin, Gi-Hong; Kim, Dong-Il

2013-09-01

Two kinds of disposable bioreactors, air-lift disposable bioreactors (ADB) and wave disposable bioreactors (WDB) were compared with stirred-tank reactors (5-L STR). These bioreactors were successfully applied to transgenic rice cell cultures for the production of recombinant human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig). In both systems, a fed-batch culture method was used to produce hCTLA4Ig efficiently by feeding concentrated amino acids and production levels were enhanced when dissolved oxygen (DO) level was regulated at 30% using pure oxygen sparging. Agitation and aeration rate during cultivation in ADB and WDB were determined by the same mixing time. The results in both disposable bioreactors showed similar values in maximum cell density (11.9 gDCW/L and 12.6 gDCW/L), doubling time (4.8- and 5.0-day), and maximum hCTLA4Ig concentration (43.7 and 43.3 mg/L). Relatively higher cell viability was sustained in the ADB whereas hCTLA4Ig productivity was 1.2-fold higher than that in WDB. The productivity was improved by increasing aeration rate (0.2 vvm). Overall, our experiments demonstrate pneumatically driven disposable bioreactors are applicable for the production of recombinant proteins in plant cell cultures. These results will be useful for development and scale-up studies of disposable bioreactor systems for transgenic plant cell cultures. Copyright © 2013 Wiley Periodicals, Inc.

Production of red mold rice using a modified Nagata type koji maker.

PubMed

Chiu, Chiu-Hsia; Ni, Kuang-Huei; Guu, Yuan-Kuang; Pan, Tzu-Ming

2006-11-01

In this research, a commercial koji maker with a rotary perforated bed of 5-m diameter was modified for red mold rice production. Monascus purpureus BCRC 31499 was selected for its high production capacities of monacolin K and red pigment. The selected strain was first cultivated in a 120-l submerged type fermentor at 34 degrees C and 2 vvm aeration rate with 60 rpm agitation for 5 days using 20% liquefied rice porridge as carbon source. The high concentration red mold rice broth (>3.5 g/ml) was harvested for inocula and well mixed with cooked rice to an initial concentration of 2% v/w. The inoculated cooked rice then was directed into the modified koji maker, in which temperature and humidity profiles were kept at varied levels at different stages, respectively. Air was circulated to remove fermentation heat while the perforated bed rotated slowly for providing mild agitation. Lag phase of the Monascus sp. in the modified koji maker was determined to be 16 h by the time the koji temperature raised rapidly. Water was added into the koji bed by a water curtain at the 36th hour to keep the moisture content of the rice koji at 50% or above. At the final stage, temperature was adjusted to 34 degrees C to direct red pigment production. After 7 days, 1,200-kg high quality red mold rice was harvested per batch. Labor costs, space, and fermentation time were reduced tremendously compared with those made by traditional methods.

Calculations of combustion response profiles and oscillations

NASA Technical Reports Server (NTRS)

Priem, Richard J.; Breisacher, Kevin J.

1993-01-01

The theory and procedures for determining the characteristics of pressure oscillations in rocket engines with prescribed burning rate oscillations are presented. Pressure and velocity oscillations calculated using this procedure are presented for the Space Shuttle Main Engine (SSME) to show the influence of baffles and absorbers on the burning rate oscillations required to achieve neutral stability. Results of calculations to determine local combustion responses using detailed physical models for injection, atomization, and vaporization with gas phase oscillations in baffled and unbaffled SSME combustors are presented. The contributions of the various physical phenomena occurring in a combustor to oscillations in combustion response were determined.

Mixing regime as a key factor to determine DON formation in drinking water biological treatment.

PubMed

Lu, Changqing; Li, Shuai; Gong, Song; Yuan, Shoujun; Yu, Xin

2015-11-01

Dissolved organic nitrogen (DON) can act as precursor of nitrogenous disinfection by-products formed during chlorination disinfection. The performances of biological fluidized bed (continuous stirred tank reactor, CSTR) and bio-ceramic filters (plug flow reactor, PFR) were compared in this study to investigate the influence of mixing regime on DON formation in drinking water treatment. In the shared influent, DON ranged from 0.71mgL(-1) to 1.20mgL(-1). The two biological fluidized bed reactors, named BFB1 (mechanical stirring) and BFB2 (air agitation), contained 0.12 and 0.19mgL(-1) DON in their effluents, respectively. Meanwhile, the bio-ceramic reactors, labeled as BCF1 (no aeration) and BCF2 (with aeration), had 1.02 and 0.81mgL(-1) DON in their effluents, respectively. Comparative results showed that the CSTR mixing regime significantly reduced DON formation. This particular reduction was further investigated in this study. The viable/total microbial biomass was determined with propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) and qPCR, respectively. The results of the investigation demonstrated that the microbes in BFB2 had higher viability than those in BCF2. The viable bacteria decreased more sharply than the total bacteria along the media depth in BCF2, and DON in BCF2 accumulated in the deeper media. These phenomena suggested that mixing regime determined DON formation by influencing the distribution of viable, total biomass, and ratio of viable biomass to total biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of oxygen supply on Monascus pigments and citrinin production in submerged fermentation.

PubMed

Yang, Jian; Chen, Qi; Wang, Weiping; Hu, Jiajun; Hu, Chuan

2015-05-01

The influence of oxygen supply on Monascus pigments and citrinin production by Monascus ruber HS.4000 in submerged fermentation was studied. For Monascus cultivation with high pigments and low citrinin production, the initial growth phase, mid-stage phase, and later-stage production phase were separated by shifting oxygen supply. The optimal condition for the fermentation process in shake-flask fermentation was a three-stage rotating rate controlled strategy (0-48 h at 150 rpm, 48-108 h at 250 rpm, 108-120 h at 200 rpm) with medium volume of 100 mL added to 250 mL Erlenmeyer flasks at 30°C for 120 h cultivation. Compared to constant one-stage cultivation (medium volume of 100 mL, rotating rate of 250 rpm), the pigments were reduced by 40.4%, but citrinin was reduced by 64.2%. The most appropriate condition for the fermentation process in a 10 L fermentor is also a three-stage aeration process (0-48 h at 300 L/h, 48-96 h at 500 L/h, 96-120 h at 200 L/h) with agitation of 300 rpm at 30°C for 120 h cultivation, and 237.3 ± 5.7 U/mL pigments were produced in 120 h with 6.05 ± 0.19 mg/L citrinin in a 10 L fermentor. Compared to aeration-constant (500 L/h) cultivation, pigment production was increased by 29.6% and citrinin concentration was reduced by 79.5%. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

New instrument for on-line viscosity measurement of fermentation media.

PubMed

Picque, D; Corrieu, G

1988-01-01

In an attempt to resolve the difficult problem of on-line determination of the viscosity of non-Newtonian fermentation media, the authors have used a vibrating rod sensor mounted on a bioreactor. The sensor signal decreases nonlinearly with increased apparent viscosity. Electronic filtering of the signal damps the interfering effect of aeration and mechanical agitation. Sensor drift is very low (0.03% of measured value per hour). On the rheological level the sensor is primarily an empirical tool that must be specifically calibrated for each fermentation process. Once this is accomplished, it becomes possible to establish linear or second-degree correlations between the electrical signal from the sensor and the essential parameters of the fermentation process in question (pH of a fermented milk during acidification, concentration of extra cellular polysaccharide). In addition, by applying the power law to describe the rheological behavior of fermentation media, we observe a second-order polynomial correlation between the sensor signal and the behavior index (n).

Culture conditions and medium components for the production of mycelial biomass and exo-polysaccharides with Paecilomyces japonica in liquid culture.

PubMed

Lee, Jong Seok; Jung, Woo Chul; Park, Seok Jae; Lee, Keun Eok; Shin, Won Cheol; Hong, Eock Kee

2013-04-01

In this study, the liquid culture conditions were optimized for maximal production of mycelial biomass and exo-polysaccharide by Paecilomyces japonica. The effects of medium composition, C/N ratio and physical parameters were investigated. From these experiments, 30 g glucose, 20 g yeast extract, 0.5 g KH2PO4, and 0.1 g CuCl2 2H2O in 1-l distilled water were found to be the most suitable carbon, nitrogen, and mineral sources, respectively. The optimal temperature, initial pH, agitation, and aeration were determined to be 27°C, uncontrolled pH, 400 rpm, and 1.0 vvm, respectively. Under these optimal conditions, the maximum mycelial growth and polysaccharides production were 23.1 g/l and 2.5 g/l, respectively. Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Comparing in situ removal strategies for improving styrene bioproduction.

PubMed

McKenna, Rebekah; Moya, Luis; McDaniel, Matthew; Nielsen, David R

2015-01-01

As an important conventional monomer compound, the biological production of styrene carries significant promise with respect to creating novel sustainable materials. Since end-product toxicity presently limits styrene production by previously engineered Escherichia coli, in situ product removal by both solvent extraction and gas stripping were explored as process-based strategies for circumventing its inhibitory effects. In solvent extraction, the addition of bis(2-ethylhexyl)phthalate offered the greatest productivity enhancement, allowing net volumetric production of 836 ± 64 mg/L to be reached, representing a 320 % improvement over single-phase cultures. Gas stripping rates, meanwhile, were controlled by rates of bioreactor agitation and, to a greater extent, aeration. A periodic gas stripping protocol ultimately enabled up to 561 ± 15 mg/L styrene to be attained. Lastly, by relieving the effects of styrene toxicity, new insight was gained regarding subsequent factors limiting its biosynthesis in E. coli and strategies for future strain improvement are discussed.

Evaluation of the energy efficiency of enzyme fermentation by mechanistic modeling.

PubMed

Albaek, Mads O; Gernaey, Krist V; Hansen, Morten S; Stocks, Stuart M

2012-04-01

Modeling biotechnological processes is key to obtaining increased productivity and efficiency. Particularly crucial to successful modeling of such systems is the coupling of the physical transport phenomena and the biological activity in one model. We have applied a model for the expression of cellulosic enzymes by the filamentous fungus Trichoderma reesei and found excellent agreement with experimental data. The most influential factor was demonstrated to be viscosity and its influence on mass transfer. Not surprisingly, the biological model is also shown to have high influence on the model prediction. At different rates of agitation and aeration as well as headspace pressure, we can predict the energy efficiency of oxygen transfer, a key process parameter for economical production of industrial enzymes. An inverse relationship between the productivity and energy efficiency of the process was found. This modeling approach can be used by manufacturers to evaluate the enzyme fermentation process for a range of different process conditions with regard to energy efficiency. Copyright © 2011 Wiley Periodicals, Inc.

Pilot scale production of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) biopolymers with high molecular weight and elastomeric properties.

PubMed

Huong, Kai-Hee; Azuraini, Mat Junoh; Aziz, Nursolehah Abdul; Amirul, Al-Ashraf Abdullah

2017-07-01

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [(P(3HB-co-4HB)] copolymer receives attention as next generation biomaterial in medical application. However, the exploitation of the copolymer is still constrained since such copolymer has not yet successfully been performed in industrial scale production. In this work, we intended to establish pilot production system of the copolymer retaining the copolymer quality which has recently discovered to have novel characteristic from lab scale fermentation. An increase of agitation speed has significantly improved the copolymer accumulation efficiency by minimizing the utilization of substrates towards cell growth components. This is evidenced by a drastic increase of PHA content from 28 wt% to 63 wt% and PHA concentration from 3.1 g/L to 6.5 g/L but accompanied by the reduction of residual biomass from 8.0 g/L to 3.8 g/L. Besides, fermentations at lower agitation and aeration have resulted in reduced molecular weight and mechanical strength of the copolymer, suggesting the role of sufficient oxygen supply efficiency in improving the properties of the resulting copolymers. The K L a-based scale-up fermentation was performed successfully in maintaining the yield and the quality of the copolymers produced without a drastic fluctuation. This suggests that the scale-up based on the K L a values supported the fermentation system of P(3HB-co-4HB) copolymer production in single-stage using mixed-substrate cultivation strategy. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

A new step aeration approach towards the improvement of nitrogen removal in a full scale Carrousel oxidation ditch.

PubMed

Jin, Pengkang; Wang, Xianbao; Wang, Xiaochang; Ngo, Huu Hao; Jin, Xin

2015-12-01

Two aeration modes, step aeration and point aeration, were used in a full-scale Carrousel oxidation ditch with microporous aeration. The nitrogen removal performance and mechanism were analyzed. With the same total aeration input, both aeration modes demonstrated good nitrification outcomes with the average efficiency in removing NH4(+)-N of more than 98%. However, the average removal efficiencies for total nitrogen were 89.3% and 77.6% under step aeration and point aeration, respectively. The results indicated that an extended aerobic zone followed the aeration zones could affect the proportion of anoxic and oxic zones. The step aeration with larger anoxic zones indicated better TN removal efficiency. More importantly, step aeration provided the suitable environment for both nitrifiers and denitrifiers. The diversity and relative abundance of denitrifying bacteria under the step aeration (1.55%) was higher than that under the point aeration (1.12%), which resulted in an overall higher TN removal efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparative Research to Surface Aeration and Blasting Aeration System Based on LCC Theory

NASA Astrophysics Data System (ADS)

Liai, CHEN; Hongxun, HOU; Weibiao, FEI; Eryan, ZHAO

2017-05-01

It is difficult to select the suitable aeration system for the designers of wastewater treatment plant (WWTP). In this paper, taking two WWTPs with surface aeration systems and blasting aeration respectively for an example, LCC theory was adapted to analysis the cost of consumption and the environmental impact, which caused by the different aeration system. Research results showed that: (1) In the 20-year life cycle, the LCC mainly depended on the cost of energy consumption whatever blasting aeration system or surface aeration, while the LCC of blasting aeration system affected by the equipment maintenance cost, maintenance cost, economic losses caused by wastewater loss and environmental load in maintenance period. (2) The LCC of blasting aeration system was lower than the surface aeration in general, on the premise of the standard discharge; (3) the blasting aeration system estimated a saving of 60,0000RMB annually in costs compared with the surface aeration.

The development of furrower model blade to paddlewheel aerator for improving aeration efficiency

NASA Astrophysics Data System (ADS)

Bahri, Samsul; Praeko Agus Setiawan, Radite; Hermawan, Wawan; Zairin Junior, Muhammad

2018-05-01

The successful of intensive aquaculture is strongly influenced by the ability of the farmers to overcome the deterioration of water quality. The problem is low dissolved oxygen through aeration process. The aerator device which widely used in pond farming is paddle wheel aerator because it is the best aerator in aeration mechanism and usable driven power. However, this aerator still has a low performance of aeration, so that the cost of aerator operational for aquaculture is still high. Up to now, the effort to improve the performance of aeration was made by two-dimensional blade design. Obviously, it does not provide the optimum result due to the power requirements for aeration is directly proportional to the increase of aeration rate. The aim of this research is to develop three-dimensional model furrowed blades. Design of Furrower model blades was 1.6 cm diameter hole, 45º of vertical angle blade position and 30º of the horizontal position. The optimum performance furrowed model blades operated on the submerged blade 9 cm with 567.54 Watt of electrical power consumption and 4.322 m3 of splash coverage volume. The standard efficiency aeration is 2.72 kg O2 kWh-1. The furrowed model blades can improve the aeration efficiency of paddlewheel aerator.

Fermentative and growth performances of Dekkera bruxellensis in different batch systems and the effect of initial low cell counts in co-cultures with Saccharomyces cerevisiae.

PubMed

Meneghin, Maria Cristina; Bassi, Ana Paula Guarnieri; Codato, Carolina Brito; Reis, Vanda Renata; Ceccato-Antonini, Sandra Regina

2013-08-01

Dekkera bruxellensis is a multifaceted yeast present in the fermentative processes used for alcoholic beverage and fuel alcohol production - in the latter, normally regarded as a contaminant. We evaluated the fermentation and growth performance of a strain isolated from water in an alcohol-producing unit, in batch systems with/without cell recycling in pure and co-cultures with Saccharomyces cerevisiae. The ethanol resistance and aeration dependence for ethanol/acid production were verified. Ethanol had an effect on the growth of D. bruxellensis in that it lowered or inhibited growth depending on the concentration. Acid production was verified in agitated cultures either with glucose or sucrose, but more ethanol was produced with glucose in agitated cultures. Regardless of the batch system, low sugar consumption and alcohol production and expressive growth were found with D. bruxellensis. Despite a similar ethanol yield compared to S. cerevisiae in the batch system without cell recycling, ethanol productivity was approximately four times lower. However, with cell recycling, ethanol yield was almost half that of S. cerevisiae. At initial low cell counts of D. bruxellensis (10 and 1000 cells/ml) in co-cultures with S. cerevisiae, a decrease in fermentative efficiency and a substantial growth throughout the fermentative cycles were displayed by D. bruxellensis. Due to the peculiarity of cell repitching in Brazilian fermentation processes, D. bruxellensis is able to establish itself in the process, even when present in low numbers initially, substantially impairing bioethanol production due to the low ethanol productivity, in spite of comparable ethanol yields. Copyright © 2013 John Wiley & Sons, Ltd.

Intermittent micro-aeration control of methane emissions from an integrated vertical-flow constructed wetland during agricultural domestic wastewater treatment.

PubMed

Liu, Xiaoling; Zhang, Ke; Fan, Liangqian; Luo, Hongbing; Jiang, Mingshu; Anderson, Bruce C; Li, Mei; Huang, Bo; Yu, Lijuan; He, Guozhu; Wang, Jingting; Pu, Aiping

2018-06-16

It is very important to control methane emissions to mitigate global warming. An intermittent micro-aeration control system was used to control methane emissions from an integrated vertical-flow constructed wetland (IVCW) to treat agricultural domestic wastewater pollution in this study. The optimized intermittent micro-aeration conditions were a 20-min aeration time and 340-min non-aeration time, 3.9 m 3  h -1 aeration intensity, evenly distributed micro-aeration diffusers at the tank bottom, and an aeration period of every 6 h. Methane flux emission by intermittent micro-aeration was decreased by 60.7% under the optimized conditions. The average oxygen transfer efficiency was 26.73%. The control of CH 4 emission from IVCWs was most strongly influenced by the intermittent micro-aeration diffuser distribution, followed by aeration intensity, aeration time, and water depth. Scaling up of IVCWs is feasible in rural areas by using intermittent micro-aeration control as a mitigation measure for methane gas emissions for climate change.

[Effect of different aeration ways on migration and transformation of nitrogen in heavily polluted urban river].

PubMed

Liu, Bo; Wang, Guo-Xiang; Wang, Feng-He; Du, Xu; Ling, Fen; Xia, Jin

2011-10-01

Water and sediment samples were collected from a heavily polluted urban river in the Xianlin University Town of Nanjing. We examined the effects of different aeration ways (aerating to sediments, aerating to water) on migration and transformation of nitrogen, using the indoor experimental method. The results showed that: nitrogen release from sediments in the form of NH4(+) -N that will accumulate under anaerobic conditions with increasing temperature; the maximum accumulation of NH4(+) -N in overlying water showed that aerating to water group < aerating to sediment group < control group and the maximum concentrations reached 9.40 mg x L(-1), 11.24 mg x L(-1) and 19.30 mg x L(-1), respectively; nitrogen compounds were generally eliminated from experiment system by a process of ammonia volatilization and a combination of two processes, i. e. nitrification and denitrification under aerating conditions; aerating to sediment was more effective for nitrogen removal than aerating to water, which was removed from overlying water, pore water and sediment; at the experimental endpoint, the concentrations of NH4(+) -N in pore water and sediment were significantly decreased by 64.36% and 58.73% respectively compared with those before aeration in aerating to sediment group and that were decreased by 39.53% and 38.78% respectively in aerating to water group; during nitrogen transformation process in overlying water, start-up of nitrification was slowly under aerating conditions; it took 9 days to realize nitrification under aerating to water conditions and 16 days under sediment aeration conditions; the NO2(-) -N accumulation took place in overlying water under the condition of aeration; the sustain time of NO2(-) -N accumulating was 17 days in aerating to water group and that was 14 days in aerating to sediment group.

Nitrogen-removal performance and community structure of nitrifying bacteria under different aeration modes in an oxidation ditch.

PubMed

Guo, Chang-Zi; Fu, Wei; Chen, Xue-Mei; Peng, Dang-Cong; Jin, Peng-Kang

2013-07-01

Oxidation-ditch operation modes were simulated using sequencing batch reactors (SBRs) with alternate stirring and aerating. The nitrogen-removal efficiencies and nitrifying characteristics of two aeration modes, point aeration and step aeration, were investigated. Under the same air-supply capacity, oxygen dissolved more efficiently in the system with point aeration, forming a larger aerobic zone. The nitrifying effects were similar in point aeration and step aeration, where the average removal efficiencies of NH4(+) N were 98% and 96%, respectively. When the proportion of anoxic and oxic zones was 1, the average removal efficiencies of total nitrogen (TN) were 45% and 66% under point aeration and step aeration, respectively. Step aeration was more beneficial to both anoxic denitrification and simultaneous nitrification and denitrification (SND). The maximum specific ammonia-uptake rates (AUR) of point aeration and step aeration were 4.7 and 4.9 mg NH4(+)/(gMLVSS h), respectively, while the maximum specific nitrite-uptake rates (NUR) of the two systems were 7.4 and 5.3 mg NO2(-)-N/(gMLVSS h), respectively. The proportions of ammonia-oxidizing bacteria (AOB) to all bacteria were 5.1% under point aeration and 7.0% under step aeration, and the proportions of nitrite-oxidizing bacteria (NOB) reached 6.5% and 9.0% under point and step aeration, respectively. The dominant genera of AOB and NOB were Nitrosococcus and Nitrospira, which accounted for 90% and 91%, respectively, under point aeration, and the diversity of nitrifying bacteria was lower than under step aeration. Point aeration was selective of nitrifying bacteria. The abundance of NOB was greater than that of AOB in both of the operation modes, and complete transformation of NH4(+) N to NO3(-)-N was observed without NO2(-)-N accumulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Aerated Lagoons. Student Manual. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Andersen, Lorri

This student manual contains the textual material for a unit which focuses on the structural and operationally unique features of aerated lagoons. Topic areas discussed include: (1) characteristics of completely mixed aerated lagoons; (2) facultative aerated lagoons; (3) aerated oxidation ponds; (4) effects of temperature on aerated lagoons; (5)…

Effectiveness of aeration and mixing in the remediation of a saline stratified river.

PubMed

Lamping, Jens; Worrall, Fred; Morgan, Huw; Taylor, Sam

2005-09-15

This study examines the use of an aeration scheme to remediate low oxygen conditions in a saline stratified system. The Tawe estuary was impounded in 1992 and quickly developed saline stratification during the summer months which led to an anoxic hypolimnon. In 1998 trials began in which a suite of aerators was applied to remediate the water quality; the trial was later extended to a full aeration scheme. This study examines pre-aeration conditions in order to delineate conditions under which poor water quality would develop, and would therefore be the conditions when aeration would be necessary. Furthermore, the study compared identical periods within the impoundment during which the following conditions existed: no aeration; and aeration with first 44, then 88, aerators. The study shows that (i) destratification occurred naturally under flows of >10 m3/s, and no low dissolved oxygen conditions were observed at higher flows; (ii) the presence of all levels of aeration had a statistically significant effect upon dissolved oxygen (DO) levels; the effect of increasing the number of aerators was approximately linear; (iii) the average effect of aeration was an increase of up to 3 mg/L DO in the deepest water; (iv) the frequency of low DO conditions decreased from 19% to 3% with the operation of aerators; and (v) aeration is most effective during periods of no tidal incursion and further from the saline water source. This study is the first to demonstrate the effectiveness of aeration in a saline stratified system.

Production of baker's yeast using date juice.

PubMed

Beiroti, A; Hosseini, S N

2007-07-01

Baker's yeast is an important additive among the products which improves bread quality and for present time is being produced in different countries by batch, fed batch or continuous cultures. Saccharomyces cerevisiae is used in fermentation of starch in dough, giving a favourable taste and produces a variety of vitamins and proteins. The main ingredient in yeast production is carbon source such as beet molasses, cane molasses, and so on. Since beet molasses has other major function as in high yield alcohol production and also due to the bioenvironmental issues and related wastewater treatment, the use of other carbohydrate sources may be considered. One of these carbohydrate sources is date which is wasted a great deal annually in this country (Iran) . In this study, the capability of date to act as a suitable carbon sources was investigated. The waste date turned into juice and consequently production and growth rate of Sacchromyces cervisiae were studied with this juice. A maximum possible yield of 50% was obtained by the optimum medium (P3), at pH 3.4, 30 degrees C, 1.4 vvm aeration rate and agitation of 500 r/min.

Analysis of volatile compounds produced by 2 strains of Lactococcus lactis isolated from leben (Tunisian fermented milk) using solid-phase microextraction-gas chromatography.

PubMed

Ziadi, M; Wathelet, J P; Marlier, M; Hamdi, M; Thonart, P

2008-08-01

The volatile compounds that characterize Leben during fermentation with 2 Lactococcus lactis strains (SLT6 and SLT10) in flasks, in a 100-L fermentor, and during storage at 4 degrees C, were investigated and compared to those from commercial Leben. Volatile compounds from Leben were concentrated by a Carboxen-PDMS fiber and analyzed by GC-MS. These compounds include acids, alcohols, aldehydes, ketones, sulfur compounds, and hydrocarbons. Commercial Leben presented a poor volatile profile compared to the laboratory-made Leben. The mixed culture of 2 Lactococcus lactis strains resulted in higher volatile compound formation than the single strain culture. The GC volatile profiles of Leben produced in flask and in the 100-L fermentor were similar. Changes in volatile compounds were observed during storage at 4 degrees C. The effect of culture conditions on production of volatiles by SLT6 strain was studied. Aeration (0.1 mL/min) and agitation enhanced the production of diacetyl, acetoin, 3-methylbutanal, and 3-methylbutanol. Fermentation at pH 5 had no effect on volatile production.

Growth of oleaginous Rhodotorula glutinis in an internal-loop airlift bioreactor by using lignocellulosic biomass hydrolysate as the carbon source.

PubMed

Yen, Hong-Wei; Chang, Jung-Tzu

2015-05-01

The conversion of abundant lignocellulosic biomass (LCB) to valuable compounds has become a very attractive idea recently. This study successfully used LCB (rice straw) hydrolysate as a carbon source for the cultivation of oleaginous yeast-Rhodotorula glutinis in an airlift bioreactor. The lipid content of 34.3 ± 0.6% was obtained in an airlift batch with 60 g reducing sugars/L of LCB hydrolysate at a 2 vvm aeration rate. While using LCB hydrolysate as the carbon source, oleic acid (C18:1) and linoleic acid (C18:2) were the predominant fatty acids of the microbial lipids. Using LCB hydrolysate in the airlift bioreactor at 2 vvm achieved the highest cell mass growth as compared to the agitation tank. Despite the low lipid content of the batch using LCB hydrolysate, this low cost feedstock has the potential of being adopted for the production of β-carotene instead of lipid accumulation in the airlift bioreactor for the cultivation of R. glutinis. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Enantiomeric separation of pharmaceutically important drug intermediates using a Metagenomic lipase and optimization of its large scale production.

PubMed

Kumar, Rakesh; Banoth, Linga; Banerjee, Uttam Chand; Kaur, Jagdeep

2017-02-01

In the present study, efficient enzymatic methods were developed using a recombinant metagenomic lipase (LipR1) for the synthesis of corresponding esters by the transesterification of five different pharmaceutically important secondary alcohols. The recombinant lipase (specific activity=87m6U/mg) showed maximum conversion in presence of ionic liquid with Naphthyl-ethanol (eeP=99%), Indanol and Methyl-4 pyridine methanol (eeS of 98% and 99%) respectively in 1h. Vinyl acetate was found as suitable acyl donor in transesterification reactions. It was interesting to observe that maximum eeP of 85% was observed in just 15min with 1-indanol. As this enzyme demonstrated pharmaceutical applications, attempts were made to scale up the enzyme production on a pilot scale in a 5litre bioreactor. Different physical parameters affecting enzyme production and biomass concentration such as agitation rate, aeration rate and inoculum concentration were evaluated. Maximum lipase activity of 8463U/ml was obtained at 7h of cultivation at 1 lpm, 300rpm and 1.5% inoculum. Copyright © 2016 Elsevier B.V. All rights reserved.

An Inexpensive Apparatus for Growing Photosynthetic Microorganisms in Exotic Atmospheres

NASA Astrophysics Data System (ADS)

Thomas, David J.; Herbert, Stephen K.

2005-02-01

Given the need for a light source, cyanobacteria and other photosynthetic microorganisms can be difficult and expensive to grow in large quantities. Lighted growth chambers and incubators typically cost 50-100% more than standard microbiological incubators. Self-shading of cells in liquid cultures prevents the growth of dense suspensions. Growing liquid cultures on a shaker table or lighted shaker incubator achieves greater cell densities, but adds considerably to the cost. For experiments in which gases other than air are required, the cost for conventional incubators increases even more. We describe an apparatus for growing photosynthetic organisms in exotic atmospheres that can be built relatively inexpensively (approximately $100 U.S.) using parts available from typical hardware or department stores (e.g., Wal-mart or K-mart). The apparatus uses microfiltered air (or other gases) to aerate, agitate, and mix liquid cultures, thus achieving very high cell densities (A750 > 3). Because gases are delivered to individual culture tubes, a variety of gas mixes can be used without the need for enclosed chambers. The apparatus works with liquid cultures of unicellular and filamentous species, and also works with agar slants.

Effect of aeration interval on oxygen consumption and GHG emission during pig manure composting.

PubMed

Zeng, Jianfei; Yin, Hongjie; Shen, Xiuli; Liu, Ning; Ge, Jinyi; Han, Lujia; Huang, Guangqun

2018-02-01

To verify the optimal aeration interval for oxygen supply and consumption and investigate the effect of aeration interval on GHG emission, reactor-scale composting was conducted with different aeration intervals (0, 10, 30 and 50 min). Although O 2 was sufficiently supplied during aeration period, it could be consumed to <10 vol% only when the aeration interval was 50 min, indicating that an aeration interval more than 50 min would be inadvisable. Compared to continuous aeration, reductions of the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent by 22.26-61.36%, 8.24-49.80% and 12.36-53.20%, respectively, was achieved through intermittent aeration. Specifically, both the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent were inversely proportional to the duration of aeration interval (R 2  > 0.902), suggesting that lengthening the duration of aeration interval to some extent could effectively reduce GHG emission. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of aeration method and aeration rate on greenhouse gas emissions during composting of pig feces in pilot scale.

PubMed

Jiang, Tao; Li, Guoxue; Tang, Qiong; Ma, Xuguang; Wang, Gang; Schuchardt, Frank

2015-05-01

The aim of this study was to uncover ways to mitigate greenhouse gas (GHG) emissions and reduce energy consumption during the composting process. We assessed the effects of different aeration rates (0, 0.18, 0.36, and 0.54 L/(kg dry matter (dm)·min)) and methods (continuous and intermittent) on GHG emissions. Pig feces and corn stalks were mixed at a ratio of 7:1. The composting process lasted for 10 weeks, and the compost was turned approximately every 2 weeks. Results showed that both aeration rate and method significantly affected GHG emissions. Higher aeration rates increased NH3 and N2O losses, but reduced CH4 emissions. The exception is that the CH4 emission of the passive aeration treatment was lower than that of the low aeration rate treatment. Without forced aeration, the CH4 diffusion rates in the center of the piles were very low and part of the CH4 was oxidized in the surface layer. Intermittent aeration reduced NH3 and CH4 losses, but significantly increased N2O production during the maturing periods. Intermittent aeration increased the nitrification/denitrification alternation and thus enhanced the N2O production. Forced aeration treatments had higher GHG emission rates than the passive aeration treatment. Forced aeration accelerated the maturing process, but could not improve the quality of the end product. Compared with continuous aeration, intermittent aeration could increase the O2 supply efficiency and reduced the total GHG emission by 17.8%, and this reduction increased to 47.4% when composting was ended after 36 days. Copyright © 2015. Published by Elsevier B.V.

Redox potential driven aeration during very-high-gravity ethanol fermentation by using flocculating yeast.

PubMed

Liu, Chen-Guang; Hao, Xue-Mi; Lin, Yen-Han; Bai, Feng-Wu

2016-05-10

Ethanol fermentation requires oxygen to maintain high biomass and cell viability, especially under very-high-gravity (VHG) condition. In this work, fermentation redox potential (ORP) was applied to drive the aeration process at low dissolved oxygen (DO) levels, which is infeasible to be regulated by a DO sensor. The performance and characteristics of flocculating yeast grown under 300 and 260 g glucose/L conditions were subjected to various aeration strategies including: no aeration; controlled aeration at -150, -100 and -50 mV levels; and constant aeration at 0.05 and 0.2 vvm. The results showed that anaerobic fermentation produced the least ethanol and had the highest residual glucose after 72 h of fermentation. Controlled aerations, depending on the real-time oxygen demand, led to higher cell viability than the no-aeration counterpart. Constant aeration triggered a quick biomass formation, and fast glucose utilization. However, over aeration at 0.2 vvm caused a reduction of final ethanol concentration. The controlled aeration driven by ORP under VHG conditions resulted in the best fermentation performance. Moreover, the controlled aeration could enhance yeast flocculating activity, promote an increase of flocs size, and accelerate yeast separation near the end of fermentation.

Bacterial community dynamics in aerated cow manure slurry at different aeration intensities.

PubMed

Hanajima, D; Fukumoto, Y; Yasuda, T; Suzuki, K; Maeda, K; Morioka, R

2011-12-01

This study aimed to characterize microbial community dynamics in aerated cow manure slurry at different aeration intensities. Batch aerobic treatments were set up in 5-l jar fermentor, each containing 3 l of manure slurry; the slurries were subjected to low, medium and high (50, 150 and 250 ml min(-1), respectively) aeration for 9 days. Microbial community composition was determined using terminal restriction fragment length polymorphism and a clone library targeting 16S rRNA genes. High and medium aeration accelerated organic carbon degradation in parallel with the degree of aeration intensity; however, 90% of the initial total organic carbon was retained during low-aeration treatment. During the active stages of organic carbon decomposition, clones belonging to the class Bacilli accumulated. Moreover, Bacilli accumulation occurred earlier under high aeration than under medium aeration. Organic matter degradation was mainly governed by a common microbial assemblage consisting of many lineages belonging to the class Bacilli. The timing of community development differed depending on aeration intensity. This study reports on changes in several environmentally important parameters and the principal microbial assemblage during the pollution-reducing phase of cattle manure aeration treatment. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Study on mathematical model to predict aerated power consumption in a gas-liquid stirred tank

NASA Astrophysics Data System (ADS)

Luan, Deyu; Zhang, Shengfeng; Wei, Xing; Chen, Yiming

The aerated power consumption characteristics in a transparent tank with diameter of 0.3 m and flat bottom stirred by a Rushton impeller were investigated by means of experimental measurement. The test fluid used was tap water as liquid and air as gas. Based on Weibull model, the complete correlation of aerated power with aerated flow number was established through non-linear fit analysis. The effects of aerated rate and impeller speed on aerated power consumption were made an exploration. Results show that the changeable trend of the aerated power consumption is found to be similar under different impeller speeds and impeller diameters, i.e. the aerated power is close to dropping linear at the beginning of gas input, and then the drop tendency decreases as the aerated rate increases, at the end, the aerated power is a constant on the whole as the aerated rate reaches up the loading state. The non-linear fit curve is done using the software Origin based on the experimental data. The fairly high precision of data fit is obtained, which indicates that the mathematical model established can be used to accurately predict the aerated power consumption, comparatively. The proposed research provides a valuable instruction and reference for the design and enlargement of stirred vessel.

Redox potential driven aeration during very-high-gravity ethanol fermentation by using flocculating yeast

PubMed Central

Liu, Chen-Guang; Hao, Xue-Mi; Lin, Yen-Han; Bai, Feng-Wu

2016-01-01

Ethanol fermentation requires oxygen to maintain high biomass and cell viability, especially under very-high-gravity (VHG) condition. In this work, fermentation redox potential (ORP) was applied to drive the aeration process at low dissolved oxygen (DO) levels, which is infeasible to be regulated by a DO sensor. The performance and characteristics of flocculating yeast grown under 300 and 260 g glucose/L conditions were subjected to various aeration strategies including: no aeration; controlled aeration at −150, −100 and −50 mV levels; and constant aeration at 0.05 and 0.2 vvm. The results showed that anaerobic fermentation produced the least ethanol and had the highest residual glucose after 72 h of fermentation. Controlled aerations, depending on the real-time oxygen demand, led to higher cell viability than the no-aeration counterpart. Constant aeration triggered a quick biomass formation, and fast glucose utilization. However, over aeration at 0.2 vvm caused a reduction of final ethanol concentration. The controlled aeration driven by ORP under VHG conditions resulted in the best fermentation performance. Moreover, the controlled aeration could enhance yeast flocculating activity, promote an increase of flocs size, and accelerate yeast separation near the end of fermentation. PMID:27161047

Surfactant effects on alpha-factors in aeration systems.

PubMed

Rosso, Diego; Stenstrom, Michael K

2006-04-01

Aeration in wastewater treatment processes accounts for the largest fraction of plant energy costs. Aeration systems function by shearing the surface (surface aerators) or releasing bubbles at the bottom of the tank (coarse- or fine-bubble aerators). Surfactant accumulation on gas-liquid interfaces reduces mass transfer rates, and this reduction in general is larger for fine-bubble aerators. This study evaluates mass transfer effects on the characterization and specification of aeration systems in clean and process water conditions. Tests at different interfacial turbulence regimes show higher gas transfer depression for lower turbulence regimes. Contamination effects can be offset at the expense of operating efficiency, which is characteristic of surface aerators and coarse-bubble diffusers. Results describe the variability of alpha-factors measured at small scale, due to uncontrolled energy density. Results are also reported in dimensionless empirical correlations describing mass transfer as a function of physiochemical and geometrical characteristics of the aeration process.

Aeration control of thermophilic aerobic digestion using fluorescence monitoring.

PubMed

Kim, Young-Kee; Oh, Byung-Keun

2009-01-01

The thermophilic aerobic digestion (TAD) process is recognized as an effective method for rapid waste activated sludge (WAS) degradation and the deactivation of pathogenic microorganisms. Yet, high energy costs due to heating and aeration have limited the commercialization of economical TAD processes. Previous research on autothermal thermophilic aerobic digestion (ATAD) has already reduced the heating cost. However, only a few studies have focused on reducing the aeration cost. Therefore, this study applied a two-step aeration control strategy to a fill-and-draw mode semicontinuous TAD process. The NADH-dependent fluorescence was monitored throughout the TAD experiment, and the aeration rate shifted according to the fluorescence intensity. As a result, the simple two-step aeration control operation achieved a 20.3% reduction in the total aeration, while maintaining an effective and stable operation. It is also expected that more savings can be achieved with a further reduction of the lower aeration rate or multisegmentation of the aeration rate.

A Controlled Agitation Process for Improving Quality of Canned Green Beans during Agitation Thermal Processing.

PubMed

Singh, Anika; Pratap Singh, Anubhav; Ramaswamy, Hosahalli S

2016-06-01

This work introduces the concept of a controlled agitation thermal process to reduce quality damage in liquid-particulate products during agitation thermal processing. Reciprocating agitation thermal processing (RA-TP) was used as the agitation thermal process. In order to reduce the impact of agitation, a new concept of "stopping agitations after sufficient development of cold-spot temperature" was proposed. Green beans were processed in No. 2 (307×409) cans filled with liquids of various consistency (0% to 2% CMC) at various frequencies (1 to 3 Hz) of RA-TP using a full-factorial design and heat penetration results were collected. Corresponding operator's process time to impart a 10-min process lethality (Fo ) and agitation time (AT) were calculated using heat penetration results. Accordingly, products were processed again by stopping agitations as per 3 agitation regimes, namely; full time agitation, equilibration time agitation, and partial time agitation. Processed products were photographed and tested for visual quality, color, texture, breakage of green beans, turbidity, and percentage of insoluble solids in can liquid. Results showed that stopping agitations after sufficient development of cold-spot temperatures is an effective way of reducing product damages caused by agitation (for example, breakage of beans and its leaching into liquid). Agitations till one-log temperature difference gave best color, texture and visual product quality for low-viscosity liquid-particulate mixture and extended agitations till equilibration time was best for high-viscosity products. Thus, it was shown that a controlled agitation thermal process is more effective in obtaining high product quality as compared to a regular agitation thermal process. © 2016 Institute of Food Technologists®

CFD simulation of fluid dynamic and biokinetic processes within activated sludge reactors under intermittent aeration regime.

PubMed

Sánchez, F; Rey, H; Viedma, A; Nicolás-Pérez, F; Kaiser, A S; Martínez, M

2018-08-01

Due to the aeration system, biological reactors are the most energy-consuming facilities of convectional WWTPs. Many biological reactors work under intermittent aeration regime; the optimization of the aeration process (air diffuser layout, air flow rate per diffuser, aeration length …) is necessary to ensure an efficient performance; satisfying the effluent requirements with the minimum energy consumption. This work develops a CFD modelling of an activated sludge reactor (ASR) which works under intermittent aeration regime. The model considers the fluid dynamic and biological processes within the ASR. The biological simulation, which is transient, takes into account the intermittent aeration regime. The CFD modelling is employed for the selection of the aeration system of an ASR. Two different aeration configurations are simulated. The model evaluates the aeration power consumption necessary to satisfy the effluent requirements. An improvement of 2.8% in terms of energy consumption is achieved by modifying the air diffuser layout. An analysis of the influence of the air flow rate per diffuser on the ASR performance is carried out. The results show a reduction of 14.5% in the energy consumption of the aeration system when the air flow rate per diffuser is reduced. The model provides an insight into the aeration inefficiencies produced within ASRs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Liquid inflow to a baffled cylindrical tank during weightlessness

NASA Technical Reports Server (NTRS)

Staskus, J. V.

1972-01-01

An experimental investigation was conducted in which the behavior of liquid inflow to a cylindrical tank containing inlet baffles was observed during weightlessness. A single tank radius (2 cm), inlet radius (0.2 cm), and liquid (ethanol)were used. The inlet end of the tank was hemispherical with a 30 deg convergent inlet. All the baffle configurations tested were cylindrically symmetric and mounted coaxially with the tank within the hemispherical end. Both stable and unstable inflow behavior were observed using each baffle. It was found that, depending on which of the baffles was used, the critical inflow velocity at which a transition to unstable inflow began was from 2.5 to 12 times greater than the corresponding velocity in an unbaffled tank.

Poststroke agitation and aggression and social quality of life: a case control study.

PubMed

Lau, Chieh Grace; Tang, Wai Kwong; Liu, Xiang Xin; Liang, Hua Jun; Liang, Yan; Wong, Adrian; Mok, Vincent; Ungvari, Gabor S; Wong, Ka Sing; Kim, Jong S; Paradiso, Sergio

2017-03-01

Aggression and agitation are common after a stroke. The association between agitation/aggression following stroke and Health-Related Quality of Life (HRQoL) in stroke survivors is unknown. This study aimed to examine the association between agitation/aggression and HRQoL in Chinese stroke survivors. Three hundred and twenty-four stroke patients entered this cross-sectional study. Agitation/aggression was assessed using the Chinese version of Neuropsychiatric Inventory (CNPI). HRQoL was measured with the Stroke Specific Quality of Life (SSQoL). Three months after the index stroke, agitation/aggression was found in 60 (18.5%) patients. In the agitation/aggression group, 44 patients (73.3%) showed passive agitation/aggression, whereas 16 (26.7%) displayed passive and active agitation/aggression. No patients showed only active agitation/aggression. Patients with agitation/aggression were more likely to have history of diabetes and greater severity of depression, as well as lower SSQoL total score and Personality Changes and Social Role scores. Controlling for diabetes and depression severity did not alter the above results. The Energy and Thinking scores of the SSQoL were significantly lower in the passive/active agitation/aggression group relative to the passive agitation/aggression group (adjusted for CNPI aggression/agitation score). In this study sample, agitation/aggression was preponderantly of the passive type and was associated with poorer HRQoL independently from depression or medical conditions. Patients with both passive and active agitation/aggression had lower Quality of Life (QoL) than patients with only passive agitation/aggression. The causality of the association between low QoL and agitation/aggression needs to be explored in future studies.

Air-induction aspirator-aerators cut heat loss to the atmosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hodel, A.E.

1993-04-01

The efficiency of biological treatment at the Amoco Chemical's Cedar Bayou plant's activated-sludge wastewater-treatment system was reduced when outdoor temperatures fell below 65[degrees]F. Amoco experienced microbe fragmenting and failure to settle in final clarification, especially during winter. Meeting permit standards during winter was a concern. With mechanical aerators, water is pumped upward and thrown into the air. Much heat loss in the aerated basin was from evaporation and conduction of the mechanical aerator spray. The plant's wastewater staff decided to replace the aerators with subsurface, propeller-type aerator-mixers. These air-induction, aspirating aerator-mixers employ a system that eliminates the spray action throughmore » which evaporation and conduction can occur. The aspirator-aeration systems also have saved energy. The units do not have to overcome the forces of gravity, as with mechanical, surface splasher aerators, which required more horsepower and higher energy consumption to throw the water up into the air. The new units can be conveniently turned on and off to match a fluctuating flow. Since the Cedar Bayou plant installed the system, the aspirator-aerators' subsurface mixing capabilities have made winter permit compliance a steadfast routine.« less

USING AERATION FOR CORROSION CONTROL

EPA Science Inventory

Aeration is a useful drinking water treatment process. Aeration has been used to remove hydrogen sulfide, methane, radon, iron, manganese, and volatile organic contaminants (VOCs) from drinking water. Aeration is also effective in removing carbon dioxide which directly impacts ...

[Measurement and analysis of micropore aeration system's oxygenating ability under operation condition in waste water treatment plant].

PubMed

Wu, Yuan-Yuan; Zhou, Xiao-Hong; Shi, Han-Chang; Qiu, Yong

2013-01-01

Using the aeration pool in the fourth-stage at Wuxi Lucun Waste Water Treatment Plant (WWTP) as experimental setup, off-gas method was selected to measure the oxygenating ability parameters of micropore aerators in a real WWTP operating condition and these values were compared with those in fresh water to evaluate the performance of the micropore aerators. Results showed that the micropore aerators which were distributed in different galleries of the aeration pool had significantly different oxygenating abilities under operation condition. The oxygenating ability of the micropore aerators distributed in the same gallery changed slightly during one day. Comparing with the oxygenating ability in fresh water, it decreased a lot in the real aeration pool, in more details, under the real WWTP operating condition, the values of oxygen transfer coefficient K(La) oxygenation capacity OC and oxygen utilization E(a) decreased by 43%, 57% and 76%, respectively.

Positive end-expiratory pressure at minimal respiratory elastance represents the best compromise between mechanical stress and lung aeration in oleic acid induced lung injury.

PubMed

Carvalho, Alysson Roncally S; Jandre, Frederico C; Pino, Alexandre V; Bozza, Fernando A; Salluh, Jorge; Rodrigues, Rosana; Ascoli, Fabio O; Giannella-Neto, Antonio

2007-01-01

Protective ventilatory strategies have been applied to prevent ventilator-induced lung injury in patients with acute lung injury (ALI). However, adjustment of positive end-expiratory pressure (PEEP) to avoid alveolar de-recruitment and hyperinflation remains difficult. An alternative is to set the PEEP based on minimizing respiratory system elastance (Ers) by titrating PEEP. In the present study we evaluate the distribution of lung aeration (assessed using computed tomography scanning) and the behaviour of Ers in a porcine model of ALI, during a descending PEEP titration manoeuvre with a protective low tidal volume. PEEP titration (from 26 to 0 cmH2O, with a tidal volume of 6 to 7 ml/kg) was performed, following a recruitment manoeuvre. At each PEEP, helical computed tomography scans of juxta-diaphragmatic parts of the lower lobes were obtained during end-expiratory and end-inspiratory pauses in six piglets with ALI induced by oleic acid. The distribution of the lung compartments (hyperinflated, normally aerated, poorly aerated and non-aerated areas) was determined and the Ers was estimated on a breath-by-breath basis from the equation of motion of the respiratory system using the least-squares method. Progressive reduction in PEEP from 26 cmH2O to the PEEP at which the minimum Ers was observed improved poorly aerated areas, with a proportional reduction in hyperinflated areas. Also, the distribution of normally aerated areas remained steady over this interval, with no changes in non-aerated areas. The PEEP at which minimal Ers occurred corresponded to the greatest amount of normally aerated areas, with lesser hyperinflated, and poorly and non-aerated areas. Levels of PEEP below that at which minimal Ers was observed increased poorly and non-aerated areas, with concomitant reductions in normally inflated and hyperinflated areas. The PEEP at which minimal Ers occurred, obtained by descending PEEP titration with a protective low tidal volume, corresponded to the greatest amount of normally aerated areas, with lesser collapsed and hyperinflated areas. The institution of high levels of PEEP reduced poorly aerated areas but enlarged hyperinflated ones. Reduction in PEEP consistently enhanced poorly or non-aerated areas as well as tidal re-aeration. Hence, monitoring respiratory mechanics during a PEEP titration procedure may be a useful adjunct to optimize lung aeration.

Hydraulic characterization and optimization of total nitrogen removal in an aerated vertical subsurface flow treatment wetland.

PubMed

Boog, Johannes; Nivala, Jaime; Aubron, Thomas; Wallace, Scott; van Afferden, Manfred; Müller, Roland Arno

2014-06-01

In this study, a side-by-side comparison of two pilot-scale vertical subsurface flow constructed wetlands (6.2 m(2)×0.85 m, q(i)=95 L/m(2) d, τ(n)=3.5 d) handling primary treated domestic sewage was conducted. One system (VA-i) was set to intermittent aeration while the other was aerated continuously (VAp-c). Intermittent aeration was provided to VA-i in an 8 h on/4 h off pattern. The intermittently aerated wetland, VA-i, was observed to have 70% less nitrate nitrogen mass outflow than the continuously aerated wetland, VAp-c. Intermittent aeration was shown to increase treatment performance for TN while saving 33% of running energy cost for aeration. Parallel tracer experiments in the two wetlands showed hydraulic characteristics similar to one Continuously Stirred Tank Reactor (CSTR). Intermittent aeration did not significantly affect the hydraulic functioning of the system. Hydraulic efficiencies were 78% for VAp-c and 76% for VA-i. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enhanced nitrogen removal of low C/N domestic wastewater using a biochar-amended aerated vertical flow constructed wetland.

PubMed

Zhou, Xu; Wang, Xuezhen; Zhang, Hai; Wu, Haiming

2017-10-01

Recently, vertical flow constructed wetlands (VFCWs) with intermittent aeration have been proven as an efficient technology to enhance removal efficiency of organics and nitrogen for wastewater treatment. However, the low denitrification effect in VFCWs was a problem for treating low carbon source wastewater. In this study, intermittent aeration and biochar, produced by biomass pyrolysis, was used to promote the nitrogen removal in VFCWs for low C/N domestic wastewater. Four systems, including non-aerated with non-biochar VFCW, non-aerated with biochar VFCW, aerated with non-biochar VFCW and aerated with biochar VFCW, were conducted for comparing their treatment performances. The results showed that much higher removal of COD (94.9%), NH 4 + -N (99.1%), TN (52.7%) and lower N 2 O emission (60.54μg·m -2 ·h -1 ) was obtained in aerated VFCW with biochar addition. The results suggested that adding biochar to intermittent aerated VFCWs could be an effective and appropriate strategy for low C/N wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enhancement of ultrasonic disintegration of sewage sludge by aeration.

PubMed

Zhao, He; Zhang, Panyue; Zhang, Guangming; Cheng, Rong

2016-04-01

Sonication is an effective way for sludge disintegration, which can significantly improve the efficiency of anaerobic digestion to reduce and recycle use of sludge. But high energy consumption limits the wide application of sonication. In order to improve ultrasonic sludge disintegration efficiency and reduce energy consumption, aeration was introduced. Results showed that sludge disintegration efficiency was improved significantly by combining aeration with ultrasound. The aeration flow rate, gas bubble size, ultrasonic density and aeration timing had impacts on sludge disintegration efficiency. Aeration that used in later stage of ultrasonic irradiation with low aeration flow rate, small gas bubbles significantly improved ultrasonic disintegration sludge efficiency. At the optimal conditions of 0.4 W/mL ultrasonic irradiation density, 30 mL/min of aeration flow rate, 5 min of aeration in later stage and small gas bubbles, ultrasonic sludge disintegration efficiency was increased by 45% and one third of ultrasonic energy was saved. This approach will greatly benefit the application of ultrasonic sludge disintegration and strongly promote the treatment and recycle of wastewater sludge. Copyright © 2015. Published by Elsevier B.V.

Experimental investigations of aeration efficiency in high-head gated circular conduits.

PubMed

Cihat Tuna, M; Ozkan, Fahri; Baylar, Ahmet

2014-01-01

The primary purpose of water aeration is to increase the oxygen saturation of the water. This can be achieved by using hydraulic structures because of substantial air bubble entrainment at these structures. Closed conduit aeration is a particular instance of this. While there has been a great deal of research on air-demand ratio within closed conduit, very little research has specifically addressed aeration efficiency of closed conduit. In the present work an experimental study was conducted to investigate the aeration efficiency of high-head gated circular conduits. Results showed that high-head gated circular conduits were effective for oxygen transfer. The effects of Froude number and ratio of the water cross-sectional flow area to the conduit cross-sectional area on aeration efficiency were particularly significant, whereas the effect of conduit length was only moderate. Further, a design formula for the aeration efficiency was presented relating the aeration efficiency to ratio of water cross-sectional flow area to conduit cross-sectional area and Froude number. The obtained results will be useful in future modeling processes and aid the practicing engineer in predicting aeration efficiency for design purposes.

Surfactant effects on alpha factors in full-scale wastewater aeration systems.

PubMed

Rosso, D; Larson, L E; Stenstrom, M K

2006-01-01

Aeration is an essential process in the majority of wastewater treatment processes, and accounts for the largest fraction of plant energy costs. Aeration systems can achieve wastewater oxygenation by shearing the surface (surface aerators) or releasing bubbles at the bottom of the tank (coarse- or fine-bubble aerators). Surfactants accumulate on gas-liquid interfaces and reduce mass transfer rates. This reduction in general is larger for fine-bubble aerators. This study was conducted to evaluate mass transfer effects on the characterization and specification of aeration systems in clean and process water conditions. Tests at different interfacial turbulence regimes were analysed, showing higher gas transfer depression for lower turbulence regimes. Higher turbulence regimes can offset contamination effects, at the expense of operating efficiency. This phenomenon is characteristic of surface aerators and coarse bubble diffusers and is here discussed. The results explain the variability of alpha factors measured at small scale, due to uncontrolled energy density. Results are also reported in dimensionless empirical correlations that describe mass transfer as a function of physiochemical and geometrical characteristics of the aeration process.

[Novel resources utilization technique for rural domestic refuse].

PubMed

Qiu, Cai-Di; He, Ruo; Chen, Song-Mei; Lou, Bin; Shen, Dong-Sheng

2009-03-15

In order to speed up rural domestic refuse resources utilization, intermittent aeration and continuous aeration were applied to treat rural domestic refuse after anaerobic fermentation. Three kinds of refuse were selected on base of fermentative age, i.e. three months, five months and seven months. Results showed that aeration could remove water and organic materials of the refuse effectively. Points of view on aeration, continuous aeration was better than intermittent aeration, and on the other side, water removal rate increased with ventilation and decreased with fermentative age in the condition of intermittent aeration. On organic materials removal point, it was affected by fermentative age significantly, i. e. increase of fermentative age could resulted in decrease in the removal efficiency. In conclusion, intermittent aeration of 0.06 m3/(min x m3) was considered to be feasible for treatment. The water removal efficiency of three months, five months and seven months fermentative age refuse could be up to 49.1%, 45.3% and 44.0%, and organic compound removal efficiency was 41.9%, 24.8% and 13.1%, respectively, after intermittent aeration for 21 d. Moreover, concentrated effect was presented on major nutrient ingredients, such as total nitrogen, phosphorus, and potassium during the aeration, which realized for resources utilization.

Impact of post-infiltration soil aeration at different growth stages of sub-surface trickle-irrigated tomato plants

NASA Astrophysics Data System (ADS)

Li, Yuan; Jia, Zong-xia; Niu, Wen-Quan; Wang, Jing-wei

2016-07-01

Sensitivity to low rhizosphere soil aeration may change over time and therefore plant response may also depend on different growth stages of a crop. This study quantified effects of soil aeration during 5 different periods, on growth and yield of trickle-irrigated potted single tomato plants. Irrigation levels were 0.6 to 0.7 (low level) or 0.7 to 0.8 (high level) of total water holding capacity of the pots. Soil was aerated by injecting 2.5 l of air into each pot through the drip tubing immediately after irrigation. Fresh fruit yield, above ground plant dry weight, plant height, and leaf area index response to these treatments were measured. For all these 4 response variables, means of post-infiltration aeration between 58 to 85 days after sowing were 13.4, 43.5, 13.7, and 37.7% higher than those for the non-aerated pots, respectively. The results indicated that: post-infiltration soil aeration can positively impact the yield and growth of sub-surface trickle-irrigated potted tomato plants; positive effects on plant growth can be obtained with aeration during the whole growth period or with aeration for partial periods; positive growth effects of partial periods of aeration appears to persist and result in yield benefit.

Effect of influent aeration on removal of organic matter from coffee processing wastewater in constructed wetlands.

PubMed

Rossmann, Maike; Matos, Antonio Teixeira; Abreu, Edgar Carneiro; Silva, Fabyano Fonseca; Borges, Alisson Carraro

2013-10-15

The aim of the present study was to evaluate the influence of aeration and vegetation on the removal of organic matter in coffee processing wastewater (CPW) treated in 4 constructed wetlands (CWs), characterized as follows: (i) ryegrass (Lolium multiflorum) cultivated system operating with an aerated influent; (ii) non-cultivated system operating with an aerated influent, (iii) ryegrass cultivated system operating with a non-aerated influent; and (iv) non-cultivated system operating with a non-aerated influent. The lowest average chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of 87, 84 and 73%, respectively, were obtained in the ryegrass cultivated system operating with a non-aerated influent. However, ryegrass cultivation did not influence the removal efficiency of organic matter. Artificial aeration of the CPW, prior to its injection in the CW, did not improve the removal efficiencies of organic matter. On other hand it did contribute to increase the instantaneous rate at which the maximum COD removal efficiency was reached. Although aeration did not result in greater organic matter removal efficiencies, it is important to consider the benefits of aeration on the removal of the other compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Remediation of Urban River Water by Pontederia Cordata Combined with Artificial Aeration: Organic Matter and Nutrients Removal and Root-Adhered Bacterial Communities.

PubMed

Gu, Dungang; Xu, Huan; He, Yan; Zhao, Feng; Huang, Minsheng

2015-01-01

Macrophyte combined with artificial aeration is a promising in situ remediation approach for urban rivers polluted with nutrients and organic matter. However, seasonal variations and aeration effects on phytoremediation performance and root-adhered microbial communities are still unclear. In this study, Pontederia cordata was used to treat polluted urban river water under various aeration intensities. Results showed that the highest removal efficiencies of chemical oxygen demand (COD(Cr)) and total nitrogen (TN) were attained under aeration of 30 L min(-1) in spring and summer and 15 L min(-1) in autumn, while total phosphorus (TP) removal reached maximum with aeration of 15 L min(-1) in all seasons. Moderate aeration was beneficial for increasing the diversity of root-adhered bacteria communities, and the shift of bacterial community structure was more pronounced in spring and autumn with varying aeration intensity. The dual effect, i.e. turbulence and dissolved oxygen (DO), of aeration on the removal of COD(Cr) and TN prevailed over the individual effect of DO, while DO was the most influential factor for TP removal and the root-adhered bacterial community diversity. P. cordata combined with 15 L min(-1) aeration was deemed to be the best condition tested in this study.

In situ nitrogen removal from leachate by bioreactor landfill with limited aeration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shao Liming; He Pinjing; Li Guojian

2008-07-01

The feasibility of simultaneous nitrification and denitrification in a bioreactor landfill with limited aeration was assessed. Three column reactors, simulating bioreactor landfill operations under anaerobic condition (as reference), intermittent forced aeration and enhanced natural aeration were hence established, where aerated columns passed through two phases, i.e., fresh landfill and well-decomposed landfill. The experimental results show that limited aeration decreased nitrogen loadings of leachate distinctly in the fresh landfill. In the well-decomposed landfill, the NH{sub 4}{sup +}-N of the input leachate could be nitrified completely in the aerated landfill columns. The nitrifying loadings of the column cross section reached 7.9 gmore » N/m{sup 2} d and 16.9 g N/m{sup 2} d in the simulated landfill columns of intermittent forced aeration and enhanced natural aeration, respectively. The denitrification was influenced by oxygen distribution in the landfill column. Intermittent existence of oxygen in the landfill with the intermittent forced aeration was favorable to denitrify the NO{sub 2}{sup -}-N and NO{sub 3}{sup -}-N, indicated by the high denitrification efficiency (>99%) under the condition of BOD{sub 5}/TN of more than 5.4 in leachate; locally persistent existence of oxygen in the landfill with enhanced natural aeration could limit the denitrification, indicated by relatively low denitrification efficiency of about 75% even when the BOD{sub 5}/TN in leachate had an average of 7.1.« less

Effects of aeration frequency on leachate quality and waste in simulated hybrid bioreactor landfills.

PubMed

Ko, Jae Hac; Ma, Zeyu; Jin, Xiao; Xu, Qiyong

2016-12-01

Research has been conducted to investigate the effects of daily aeration frequency on leachate quality and waste settlement in simulated hybrid landfill bioreactors. Four laboratory-scale reactors were constructed and operated for about 10 months to simulate different bioreactor operations, including one anaerobic bioreactor and three hybrid bioreactors with different aeration frequencies (one, two, and four times per day). Chemical oxygen demand (COD) and biochemical oxygen demand (BOD 5 ) reduced more than 96% of the initial concentrations in all aerated bioreactors. The differences of COD and BOD 5 reductions among tested aeration frequencies were relatively small. For ammonia nitrogen, the higher aeration frequency (two or four times per day) resulted in the quicker reduction. Overall, the concentrations of heavy metals (Cr, Co, Cu, Mn, Ni, and Zn) decreased over time except Cd and Pb. The reduction of redox-sensitive metal concentrations (Mn, Co, Ni, and Cu) was greater in aerated bioreactors than in anaerobic bioreactor. Settlement of municipal solid waste (MSW) was enhanced with higher frequency of aeration events (four times per day). In recent years, hybird bioreactor landfill technology has gained a lot of attention. Appropriate aeration rate is crucial for hybrid bioreactor operation, but few studies have been done and different results were obtained. Research was conducted to investigate the effects of daily aeration frequency on leachate quality and waste settlement. Results indicated that aeration can effectively accelerate waste stabilization and remove organic carbon concentration and total nitrogen in the leachate.

Influence of aeration implements, phosphorus fertilizers, and soil taxa on phosphorus losses from grasslands.

PubMed

Franklin, D H; Butler, D M; Cabrera, M L; Calvert, V H; West, L T; Rema, J A

2011-01-01

Attenuation of rainfall within the solum may help to move contaminants and nutrients into the soil to be better sequestered or utilized by crops. Surface application of phosphorus (P) amendments to grasslands may lead to elevated concentrations of P in surface runoff and eutrophication of surface waters. Aeration of grasslands has been proposed as a treatment to reduce losses of applied P. Here, results from two small-plot aeration studies and two field-scale, paired-watershed studies are supplemented with previously unpublished soil P data and synthesized. The overall objective of these studies was to determine the impact of aeration on soil P, runoff volume, and runoff P losses from mixed tall fescue [Lolium arundinaceum (Schreb.) Darbysh.]-bermudagrass (Cynodon dactylon L.) grasslands fertilized with P. Small-scale rainfall simulations were conducted on two soil taxa using three types of aeration implements: spikes, disks, and cores. The-field scale study was conducted on four soil taxa with slit and knife aeration. Small-plot studies showed that core aeration reduced loads of total P and dissolved reactive P (DRP) in runoff from plots fertilized with broiler litter and that aeration was effective in reducing P export when it increased soil P in the upper 5 cm. In the field-scale study, slit aeration reduced DRP losses by 35% in fields with well-drained soils but not in poorly drained soils. Flow-weighted concentrations of DRP in aerated fields were related to water-soluble P applied in amendments and soil test P in the upper 5 cm. These studies show that the overall effectiveness of mechanical soil aeration on runoff volume and P losses is controlled by the interaction of soil characteristics such as internal drainage and compaction, soil P, type of surface-applied manure, and type of aeration implement.

Catfish production using intensive aeration

USDA-ARS?s Scientific Manuscript database

For the last 3 years, researchers at UAPB and NWAC have been monitoring and verifying production yields in intensively aerated catfish ponds with aeration rates greater than 6 hp/acre. We now have three years of data on commercial catfish production in intensively aerated ponds. With stocking densi...

Effect of famine-phase reduced aeration on polyhydroxyalkanoate accumulation in aerobic granules.

PubMed

Vjayan, T; Vadivelu, V M

2017-12-01

The effects of variable aeration in the famine period on polyhydroxyalkanoate (PHA) accumulation in aerobic granules were investigated. Results showed that regardless of the aeration rates used during famine period, all aerobic granules achieved a similar chemical oxygen demand removal and PHA content. The decrease in famine-period aeration rates accelerated the maximum PHA accumulation together with increase in granular size and settling ability. The PHA-accumulating microorganisms were found to have shifted closer to the surface of the granules when the aeration rate was reduced. Moreover, PHA compositional changes occurred, where the hydroxyvalerate content had increased with the reduction in aeration rate. Ultimately, the results indicate that the requirement of aeration for PHA accumulation in aerobic granules is highly insignificant in the famine phase. PHA production in aerobic granules under zero aeration in the famine period may result in an energy input reduction of up to 74%. Copyright © 2017 Elsevier Ltd. All rights reserved.

Improving microalgal growth with reduced diameters of aeration bubbles and enhanced mass transfer of solution in an oscillating flow field.

PubMed

Yang, Zongbo; Cheng, Jun; Lin, Richen; Zhou, Junhu; Cen, Kefa

2016-07-01

A novel oscillating gas aerator combined with an oscillating baffle was proposed to generate smaller aeration bubbles and enhance solution mass transfer, which can improve microalgal growth in a raceway pond. A high-speed photography system (HSP) was used to measure bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure mass-transfer coefficient and mixing time. Bubble diameter and generation time decreased with decreased aeration gas rate, decreased orifice diameter, and increased water velocity in the oscillating gas aerator. The optimized oscillating gas aerator decreased bubble diameter and generation time by 25% and 58%, respectively, compared with a horizontal tubular gas aerator. Using an oscillating gas aerator and an oscillating baffle in a raceway pond increased the solution mass-transfer coefficient by 15% and decreased mixing time by 32%; consequently, microalgal biomass yield increased by 19%. Copyright © 2016 Elsevier Ltd. All rights reserved.

Production of ethanol and arabitol by Debaryomyces nepalensis: influence of process parameters

PubMed Central

2013-01-01

Debaryomyces nepalensis, osmotolerant yeast isolated from rotten apple, is known to utilize both hexoses and pentoses and produce industrially important metabolites like ethanol, xylitol and arabitol. In the present study, the effect of different growth substrates, trace elements, nitrogen concentration and initial pH on growth and formation of ethanol and arabitol were examined. Optimum conditions for maximizing the product yields were established: glucose as carbon source, an initial pH of 6.0, 6 g/L of ammonium sulphate and addition of micronutrients. Under these best suited conditions, a concentration of 11g/L of arabitol and 19 g/L of ethanol was obtained in shake flask fermentations. The fermentation was scaled up to 2.5 L bioreactor and the influence of aeration, agitation and initial substrate concentration was also determined. Under optimal conditions (150 g/L glucose, 400 rpm and 0.5 vvm) ethanol concentration reached 52 g/L, which corresponds to a yield of 0.34 g/g and volumetric productivity of 0.28 g/L/h, whereas arabitol production reached a maximum of 14 g/L with a yield and volumetric productivity of 0.1 g/g and 0.07 g/L/h respectively. PMID:23659479

[Advances in microbial production of alkaline polygalacturonate lyase and its application in clean production of textile industry].

PubMed

Liu, Long; Wang, Zhihao; Zhang, Dongxu; Li, Jianghua; Du, Guocheng; Chen, Jian

2009-12-01

We reviewed the microbial production of alkaline polygalacturonate lyase (PGL) and its application in the clean production of textile industry. Currently PGL is mainly produced by microbial fermentation and Bacillus sp. is an ideal wild strain for PGL production. Microbial PGL production was affected by many factors including the concentration and feeding mode of substrate, cell concentration, agitation speed, aeration rate, pH and temperature. Constructing the recombinant strain provided an effective alternative for PGL production, and the concentration of PGL produced by the recombinant Pichia pastoris reached 1305 U/mL in 10 m3 fermentor. The recombinant Pichia pastoris had the potential to reach the industrial production of PGL. PGL can be applied in bio-scouring process in the pre-treatment of cotton. Compared with the traditional alkaline cooking process, the application of PGL can protect fiber, improve the bio-scouring efficiency, decrease energy consumption and alleviate the environmental pollution. The future research focus will be the molecular directed evolution of PGL to make PGL more suitable for the application of PGL in bio-scouring process to realize the clean production of textile industry.

Feasibility of an in situ measurement device for bubble size and distribution.

PubMed

Junker, Beth; Maciejak, Walter; Darnell, Branson; Lester, Michael; Pollack, Michael

2007-09-01

The feasibility of in situ measurement device for bubble size and distribution was explored. A novel in situ probe measurement system, the EnviroCam, was developed. Where possible, this probe incorporated strengths, and minimized weaknesses of historical and currently available real-time measurement methods for bubbles. The system was based on a digital, high-speed, high resolution, modular camera system, attached to a stainless steel shroud, compatible with standard Ingold ports on fermenters. Still frames and/or video were produced, capturing bubbles passing through the notch of the shroud. An LED light source was integral with the shroud. Bubbles were analyzed using customized commercially available image analysis software and standard statistical methods. Using this system, bubble sizes were measured as a function of various operating parameters (e.g., agitation rate, aeration rate) and as a function of media properties (e.g., viscosity, antifoam, cottonseed flour, and microbial/animal cell broths) to demonstrate system performance and its limitations. For selected conditions, mean bubble size changes qualitatively compared favorably with published relationships. Current instrument measurement capabilities were limited primarily to clear solutions that did not contain large numbers of overlapping bubbles.

Two-Step Production of Phenylpyruvic Acid from L-Phenylalanine by Growing and Resting Cells of Engineered Escherichia coli: Process Optimization and Kinetics Modeling.

PubMed

Hou, Ying; Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-Dong; Liu, Long; Du, Guocheng; Chen, Jian

2016-01-01

Phenylpyruvic acid (PPA) is widely used in the pharmaceutical, food, and chemical industries. Here, a two-step bioconversion process, involving growing and resting cells, was established to produce PPA from l-phenylalanine using the engineered Escherichia coli constructed previously. First, the biotransformation conditions for growing cells were optimized (l-phenylalanine concentration 20.0 g·L-1, temperature 35°C) and a two-stage temperature control strategy (keep 20°C for 12 h and increase the temperature to 35°C until the end of biotransformation) was performed. The biotransformation conditions for resting cells were then optimized in 3-L bioreactor and the optimized conditions were as follows: agitation speed 500 rpm, aeration rate 1.5 vvm, and l-phenylalanine concentration 30 g·L-1. The total maximal production (mass conversion rate) reached 29.8 ± 2.1 g·L-1 (99.3%) and 75.1 ± 2.5 g·L-1 (93.9%) in the flask and 3-L bioreactor, respectively. Finally, a kinetic model was established, and it was revealed that the substrate and product inhibition were the main limiting factors for resting cell biotransformation.

Impact of intermittent aerations on leachate quality and greenhouse gas reduction in the aerobic-anaerobic landfill method.

PubMed

Nag, Mitali; Shimaoka, Takayuki; Komiya, Teppei

2016-09-01

The aerobic-anaerobic landfill method (AALM) is a novel approach in solid waste management that could shorten the landfill post-closure period and minimize the environmental loads. In this study, the aerobic-anaerobic landfill method was evaluated by using intermittent aeration. In addition, the nitrification-denitrification process was assessed as a means of reducing the emission of greenhouse gases (GHGs) and improving the leachate quality during the degradation of the organic solid waste. The leachate quality and the gas composition in each of the reactors were measured during the experimental period (408days). The aeration process entailed the injection of air into plexiglass cylinders (200cm height×10 cm diameter), filled with fresh organic solid waste collected from a composting plant. Different aeration routines were applied, namely, continuous aeration (aerobic reactor A), aeration for three days/week (aerobic-anaerobic reactor B), aeration for 6h/day (aerobic-anaerobic reactor C), and no aeration (non-aerated reactor D). It was found that aerobic reactor A produced the best results in terms of reduction of GHGs and improvement of the leachate quality. The aerobic-anaerobic reactor C was found to be more effective than reactor B in respect of both the emission of GHGs and the leachate quality; moreover, compared with aerobic reactor A, energy costs were reduced by operating this reactor. The transition period phenomenon was investigated during an intensive seven-day experiment conducted on the discharged leachate obtained from aerobic-anaerobic reactors B and C. The experiment concerned the differences in the composition of the gas during the aeration and the non-aeration periods. It was found that the transition period between the aeration and non-aeration cycles, which followed the simultaneous nitrification-denitrification had a considerable effect on the leachate quality of both the reactors. The results indicated that AALM has the potential to reduce leachate pollutants and the emission of GHGs. Furthermore, the occurrence of simultaneous nitrification-denitrification presents the prospect that intermittent aeration could reduce landfill aftercare and energy costs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization of micro-aeration intensity in acidogenic reactor of a two-phase anaerobic digester treating food waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Suyun; Sino-Forest Applied Research Centre for Pearl River Delta Environment, Department of Biology, Hong Kong Baptist University, Hong Kong Special Administrative Region; Selvam, Ammaiyappan

Highlights: • Effect of micro-aeration on acidogenesis and hydrolysis of food waste was investigated. • Micro-aeration at 258 L-air/kg TS/d increased the VFAs production 3-fold. • High aeration leads to loss of substrate through microbial biomass and respiration. • Optimum aeration increased methane recovery while high aeration intensity reduced methane yield. - Abstract: Micro-aeration is known to promote the activities of hydrolytic exo-enzymes and used as a strategy to improve the hydrolysis of particulate substrate. The effect of different micro-aeration rates, 0, 129, 258, and 387 L-air/kg TS/d (denoted as LBR-AN, LBR-6h, LBR-3h and LBR-2h, respectively) on the solubilization ofmore » food waste was evaluated at 35 °C in four leach bed reactors (LBR) coupled with methanogenic upflow anaerobic sludge blanket (UASB) reactor. Results indicate that the intensity of micro-aeration influenced the hydrolysis and methane yield. Adequate micro-aeration intensity in LBR-3h and LBR-2h significantly enhanced the carbohydrate and protein hydrolysis by 21–27% and 38–64% respectively. Due to the accelerated acidogenesis, more than 3-fold of acetic acid and butyric acid were produced in LBR-3h as compared to the anaerobic treatment LBR-AN resulting in the maximum methane yield of 0.27 L CH{sub 4}/g VS{sub added} in the UASB. The performance of LBR-6h with inadequate aeration was similar to that of LBR-AN with a comparable hydrolysis degree. Nevertheless, higher aeration intensity in LBR-2h was also unfavorable for methane yield due to significant biomass generation and CO{sub 2} respiration of up to 18.5% and 32.8% of the total soluble hydrolysate, respectively. To conclude, appropriate micro-aeration rate can promote the hydrolysis of solid organic waste and methane yield without undesirable carbon loss and an aeration intensity of 258 L-air/kg TS/d is recommended for acidogenic LBR treating food waste.« less

Yields and Nutritional of Greenhouse Tomato in Response to Different Soil Aeration Volume at two depths of Subsurface drip irrigation

PubMed Central

Li, Yuan; Niu, Wenquan; Dyck, Miles; Wang, Jingwei; Zou, Xiaoyang

2016-01-01

This study investigated the effects of 4 aeration levels (varied by injection of air to the soil through subsurface irrigation lines) at two subsurface irrigation line depths (15 and 40 cm) on plant growth, yield and nutritional quality of greenhouse tomato. In all experiments, fruit number, width and length, yield, vitamin C, lycopene and sugar/acid ratio of tomato markedly increased in response to the aeration treatments. Vitamin C, lycopene, and sugar/acid ratio increased by 41%, 2%, and 43%, respectively, in the 1.5 times standard aeration volume compared with the no-aeration treatment. An interaction between aeration level and depth of irrigation line was also observed with yield, fruit number, fruit length, vitamin C and sugar/acid ratio of greenhouse tomato increasing at each aeration level when irrigation lines were placed at 40 cm depth. However, when the irrigation lines were 15 cm deep, the trend of total fruit yields, fruit width, fruit length and sugar/acid ratio first increased and then decreased with increasing aeration level. Total soluble solids and titrable acid decreased with increasing aeration level both at 15 and 40 cm irrigation line placement. When all of the quality factors, yields and economic benefit are considered together, the combination of 40 cm line depth and “standard” aeration level was the optimum combination. PMID:27995970

Directional Flow of Summer Aeration to Manage Insect Pests in Stored Wheat

USDA-ARS?s Scientific Manuscript database

Field trials were conducted in metal wheat storage bins to determine whether pressure aeration, pushing ambient air from the bottom, or suction aeration, pulling air down from the top, would be more efficient at cooling the wheat mass and thereby limiting insect population growth. Aeration was accom...

Temperature stratification and insect pest populations in stored wheat with suction versus pressure aeration

USDA-ARS?s Scientific Manuscript database

A three-year study was conducted to compare temperature profiles in the headspace and in the bulk mass of wheat aerated through pressure aeration and suction aeration. Insect pitfall traps were used to measure naturally-occurring populations of stored product insects. Results show uniform distributi...

Incidence, Risk Factors and Consequences of Emergence Agitation in Adult Patients after Elective Craniotomy for Brain Tumor: A Prospective Cohort Study

PubMed Central

Chen, Lu; Xu, Ming; Li, Gui-Yun; Cai, Wei-Xin; Zhou, Jian-Xin

2014-01-01

Emergence agitation is a frequent complication that can have serious consequences during recovery from general anesthesia. However, agitation has been poorly investigated in patients after craniotomy. In this prospective cohort study, adult patients were enrolled after elective craniotomy for brain tumor. The sedation-agitation scale was evaluated during the first 12 hours after surgery. Agitation developed in 35 of 123 patients (29%). Of the agitated patients, 28 (80%) were graded as very and dangerously agitated. By multivariate stepwise logistic regression analysis, independent predictors for agitation included male sex, history of long-term use of anti-depressant drugs or benzodiazepines, frontal approach of the operation, method and duration of anesthesia and presence of endotracheal intubation. Total intravenous anesthesia and balanced anesthesia with short duration were protective factors. Emergence agitation was associated with self-extubation (8.6% vs 0%, P = 0.005). Sedatives were administered more in agitated patients than non-agitated patients (85.7% vs 6.8%, P<0.001). In conclusion, emergence agitation was a frequent complication in patients after elective craniotomy for brain tumors. The clarification of risk factors could help to identify the high-risk patients, and then to facilitate the prevention and treatment of agitation. For patients undergoing craniotomy, greater attention should be paid to those receiving a frontal approach for craniotomy and those anesthetized under balanced anesthesia with long duration. More researches are warranted to elucidate whether total intravenous anesthesia could reduce the incidence of agitation after craniotomy. Trial Registration ClinicalTrials.gov NCT00590499. PMID:25493435

The Study of Micro-Pressure Inner-Loop Bioreactor Oxygen Mass Transfer Characteristics

NASA Astrophysics Data System (ADS)

Wan, L. G.; Lin, Q.; Bian, D. J.; Ren, Q. K.; Xiao, Y. B.; Lu, W. X.

2018-03-01

The oxygen mass transfer characteristics in a Micro-Pressure Inner-Loop bioreactor (MPR) were studied by clean water oxygenation experiment, the results show that when the aeration adopt by 0.1, 0.2, 0.4, 0.6 m3·h-1, respectively, the oxygen mass transfer coefficient KLa(20) in the reactor increases with the increase of the aeration. KLa(20) shows a good linear correlation with the aeration. The rate is 0.2128 h·m-3·min-1 and the correlation coefficient R=0.993. However, the trend of EO2 increases first and then decreases with the increase of aeration. When the aeration increased to 0.4 m3·h-1, the EO2 reaches the maximum. If aeration increases constantly, EO2 begin to decrease excessive aeration may lead to an increase in energy waste during reactor operation.

Enhancing recovery of ammonia from swine manure anaerobic digester effluent using gas-permeable membrane technology.

PubMed

Dube, P J; Vanotti, M B; Szogi, A A; García-González, M C

2016-03-01

Gas-permeable membrane technology is useful to recover ammonia from manure. In this study, the technology was enhanced using aeration instead of alkali chemicals to increase pH and the ammonium (NH4(+)) recovery rate. Digested effluents from covered anaerobic swine lagoons containing 1465-2097 mg NH4(+)-N L(-1) were treated using submerged membranes (0.13 cm(2) cm(-3)), low-rate aeration (120 mL air L-manure(-1) min(-1)) and nitrification inhibitor (22 mg L(-1)) to prevent nitrification. The experiment included a control without aeration. The pH of the manure with aeration rose from 8.6 to 9.2 while the manure without aeration decreased from 8.6 to 8.1. With aeration, 97-99% of the NH4(+) was removed in about 5 days of operation with 96-98% recovery efficiency. In contrast, without aeration it took 25 days to treat the NH4(+). Therefore, the recovery of NH4(+) was five times faster with the low-rate aeration treatment. This enhancement could reduce costs by 70%. Published by Elsevier Ltd.

Study of the liquid-film-forming apparatus as an alternative aeration system: design criteria and operating condition.

PubMed

Hongprasith, Narapong; Imai, Tsuyoshi; Painmanakul, Pisut

2017-06-01

Aeration is an important factor in aquaculture systems because it is a vital condition for all organisms that live in water and respire aerobically. Generally, mechanical surface aerators are widely used in Thailand due to their advantage for increasing dissolved oxygen (DO) and for their horizontal mixing of aquaculture ponds with large surface areas. However, these systems still have some drawbacks, primarily the low oxygen transfer efficiency (OTE) and energy. Regarding this issue, alternative aeration systems should be studied and applied. Therefore, this research aims to study the aeration mechanism obtained by the diffused-air aeration combined with a liquid-film-forming apparatus (LFFA). The effect of gas flow rates, types, and patterns of aerator installation were investigated in an aquaculture pond of 10 m × 10 m × 1.5 m. The analytical parameters were volumetric mass transfer coefficient (k L a), OTE, and aeration efficiency (AE). From the results, the '4-D' with partitions was proposed as the suitable pattern for the LFFA installation. The advantage could be obtained from high energy performance with 1.2 kg/kW h of AE. Then, the operation conditions can be applied as a design guideline for this alternative aeration system in the aquaculture ponds.

Landfill aeration in the framework of a reclamation project in Northern Italy.

PubMed

Raga, Roberto; Cossu, Raffaello

2014-03-01

In situ aeration by means of the Airflow technology was proposed for landfill conditioning before landfill mining in the framework of a reclamation project in Northern Italy. A 1-year aeration project was carried out on part of the landfill with the objective of evaluating the effectiveness of the Airflow technology for landfill aerobization, the evolution of waste biological stability during aeration and the effects on leachate and biogas quality and emissions. The main outcomes of the 1-year aeration project are presented in the paper. The beneficial effect of the aeration on waste biological stability was clear (63% reduction of the respiration index); however, the effectiveness of aeration on the lower part of the landfill is questionable, due to the limited potential for air migration into the leachate saturated layers. During the 1-year in situ aeration project approx. 275 MgC were discharged from the landfill body with the extracted gas, corresponding to 4.6 gC/kgDM. However, due to the presence of anaerobic niches in the aerated landfill, approx. 46% of this amount was extracted as CH4, which is higher than reported in other aeration projects. The O2 conversion quota was lower than reported in other similar projects, mainly due to the higher air flow rates applied. The results obtained enabled valuable recommendations to be made for the subsequent application of the Airflow technology to the whole landfill. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bioreactor tests preliminary to landfill in situ aeration: A case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raga, Roberto, E-mail: roberto.raga@unipd.it; Cossu, Raffaello

Highlights: ► Carbon and nitrogen mass balances in aerated landfill simulation reactors. ► Waste stabilization in aerated landfill simulation reactors. ► Effect of temperature on biodegradation processes in aerated landfills. - Abstract: Lab scale tests in bioreactor were carried out in the framework of the characterization studies of a landfill where in situ aeration (possibly followed by landfill mining) had been proposed as part of the novel waste management strategy in a region in northern Italy. The tests were run to monitor the effects produced by aerobic conditions at different temperatures on waste sampled at different depths in the landfill,more » with focus on the carbon and nitrogen conversion during aeration. Temperatures ranging from 35 to 45 °C were chosen, in order to evaluate possible inhibition of biodegradation processes (namely nitrification) at 45 °C in the landfill. The results obtained showed positive effects of the aeration on leachate quality and a significant reduction of waste biodegradability. Although a delay of biodegradation processes was observed in the reactor run at 45 °C, biodegradation rates increased after 2 months of aeration, providing very low values of the relevant parameters (as in the other aerated reactors) by the end of the study. Mass balances were carried out for TOC and N-NH{sub 4}{sup +}; the findings obtained were encouraging and provided evidence of the effectiveness of carbon and nitrogen conversion processes in the aerated landfill simulation reactors.« less

Study on low intensity aeration oxygenation model and optimization for shallow water

NASA Astrophysics Data System (ADS)

Chen, Xiao; Ding, Zhibin; Ding, Jian; Wang, Yi

2018-02-01

Aeration/oxygenation is an effective measure to improve self-purification capacity in shallow water treatment while high energy consumption, high noise and expensive management refrain the development and the application of this process. Based on two-film theory, the theoretical model of the three-dimensional partial differential equation of aeration in shallow water is established. In order to simplify the equation, the basic assumptions of gas-liquid mass transfer in vertical direction and concentration diffusion in horizontal direction are proposed based on engineering practice and are tested by the simulation results of gas holdup which are obtained by simulating the gas-liquid two-phase flow in aeration tank under low-intensity condition. Based on the basic assumptions and the theory of shallow permeability, the model of three-dimensional partial differential equations is simplified and the calculation model of low-intensity aeration oxygenation is obtained. The model is verified through comparing the aeration experiment. Conclusions as follows: (1)The calculation model of gas-liquid mass transfer in vertical direction and concentration diffusion in horizontal direction can reflect the process of aeration well; (2) Under low-intensity conditions, the long-term aeration and oxygenation is theoretically feasible to enhance the self-purification capacity of water bodies; (3) In the case of the same total aeration intensity, the effect of multipoint distributed aeration on the diffusion of oxygen concentration in the horizontal direction is obvious; (4) In the shallow water treatment, reducing the volume of aeration equipment with the methods of miniaturization, array, low-intensity, mobilization to overcome the high energy consumption, large size, noise and other problems can provide a good reference.

The in situ aeration in an old landfill in China: Multi-wells optimization method and application.

PubMed

Liu, Lei; Ma, Jun; Xue, Qiang; Shao, Jingbang; Chen, Yijun; Zeng, Gang

2018-06-01

The optimization design of well spacing (WS) and aeration rate (AR) is crucial to the in situ aeration system operation in under long-term and high-efficiency conditions. This optimization design aims to transport additional air into landfills and to develop an improved oxygen environment for enhancing aerobic degradation. Given the specific pore structure distribution within landfills, providing sufficient oxygen in all waste bodies in field sites through gas wells is difficult. The design of well distribution also lacks adequate criteria. In this work, the multi-well optimization aeration method (MWOAM) was proposed to select the WS and AR from prediction results that consider gas transport properties by maximizing oxygen storage ratio (OSR) as the key objective threshold. This method was applied to the aeration restoration engineering in Jinkou landfill, which represents the first full-scale application of an aeration project in China, to optimize the operation scheme of the aeration system. Results of the gas concentration monitoring show that the trend of the OSR with aeration time based on the measurement agrees with the prediction. The oxygen and methane contents remain high and low within the landfill during the aeration process, respectively. Moreover, the temperature in the waste body did not exceed the upper limit value. These results suggested that the MWOAM is an effective means of supplying sufficient oxygen content across the landfill body and extend the aeration system operation for the long term. Therefore, this work provides reliable evidence to support the design and operation management of the aeration systems in full-scale landfills. Copyright © 2018 Elsevier Ltd. All rights reserved.

A novel circulating loop bioreactor with cells immobilized in loofa ( Luffa cylindrica) sponge for the bioconversion of raw cassava starch to ethanol.

PubMed

Roble, N D; Ogbonna, J C; Tanaka, H

2003-02-01

A circulating loop bioreactor (CLB) with cells immobilized in loofa sponge was constructed for simultaneous aerobic and anaerobic processes. The CLB consists of an aerated riser and a non-aerated downcomer column connected at the top and bottom by cylindrical pipes. Ethanol production from raw cassava starch was investigated in the CLB. Aspergillus awamori IAM 2389 and Saccharomyces cerevisiae IR2 immobilized on loofa sponge were placed, respectively, in the aerated riser column and non-aerated downcomer column. Both alpha-amylase and glucoamylase activities increased as the aeration rate was increased. Ethanol yield and productivity increased with an increase in the aeration rate up to 0.5 vvm, but decreased at higher aeration rates. The CLB was operated at an aeration rate of 0.5 vvm for more than 600 h, resulting in an average ethanol productivity and yield from raw cassava starch of 0.5 g-ethanol l(-1) x h(-1) and 0.45 g ethanol/g starch, respectively. In order to increase ethanol productivity, it was necessary to increase the dissolved oxygen (DO) concentration in the riser column and decrease the DO concentration in the downcomer column. However, increasing the aeration rate resulted in increases in the DO concentration in both the riser and the downcomer columns. At high aeration rate, there was no significant difference in the DO concentration in the riser and downcomer columns. The aeration rate was therefore uncoupled from the liquid circulation by attaching a time-controlled valve in the upper connecting pipe. By optimizing the time and frequency of valve opening, and operation at high aeration rate, it was possible to maintain a very high DO concentration in the riser column and a low DO concentration in the downcomer column. Under these conditions, ethanol productivity increased by more than 100%, to 1.17 g l(-1) x h(-1).

Production of a recombinant phospholipase A2 in Escherichia coli using resonant acoustic mixing that improves oxygen transfer in shake flasks.

PubMed

Valdez-Cruz, Norma A; Reynoso-Cereceda, Greta I; Pérez-Rodriguez, Saumel; Restrepo-Pineda, Sara; González-Santana, Jesus; Olvera, Alejandro; Zavala, Guadalupe; Alagón, Alejandro; Trujillo-Roldán, Mauricio A

2017-07-25

Shake flasks are widely used during the development of bioprocesses for recombinant proteins. Cultures of recombinant Escherichia coli with orbital mixing (OM) have an oxygen limitation negatively affecting biomass growth and recombinant-protein production. With the aim to improve mixing and aeration in shake flask cultures, we analyzed cultures subjected to OM and the novel resonant acoustic mixing (RAM) by applying acoustic energy to E. coli BL21-Gold (DE3): a producer of recombinant phospholipase A2 (rPLA2) from Micrurus laticollaris snake venom. Comparing OM with RAM (200 rpm vs. 7.5g) at the same initial volumetric oxygen transfer coefficient (k L a ≈ 80 h -1 ) ~69% less biomass was obtained with OM compared with RAM. We analyzed two more conditions increasing agitation until maximal speed (12.5 and 20g), and ~1.6- and ~1.4-fold greater biomass was obtained as compared with cultures at 7.5g. Moreover, the specific growth rate was statistically similar in all cultures carried out in RAM, but ~1.5-fold higher than that in cultures carried out under OM. Almost half of the glucose was consumed in OM, whereas between 80 and 100% of the glucose was consumed in RAM cultures, doubling biomass per glucose yields. Differential organic acid production was observed, but acetate production was prevented at the maximal RAM (20g). The amount of rPLA2 in both, OM and RAM cultures, represented 38 ± 5% of the insoluble protein. A smaller proportion of α-helices and β-sheet of purified inclusion bodies (IBs) were appreciated by ATR-FTIR from cultures carried out under OM, than those from RAM. At maximal agitation by RAM, internal E. coli localization patterns of protein aggregation changed, as well as, IBs proteolytic degradation, in conjunction with the formation of small external vesicles, although these changes did not significantly affect the cell survival response. In moderate-cell-density recombinant E. coli BL21-Gold (DE3) cultures, the agitation increases in RAM (up to the maximum) was not enough to avoid the classical oxygen limitation that happens in OM shake flasks. However, RAM presents a decrease of oxygen limitation, resulting in a favorable effect on biomass growth and volumetric rPLA2 production. While under OM a higher recombinant protein yield was obtained.

Ketamine as a first-line treatment for severely agitated emergency department patients.

PubMed

Riddell, Jeff; Tran, Alexander; Bengiamin, Rimon; Hendey, Gregory W; Armenian, Patil

2017-07-01

Emergency physicians often need to control agitated patients who present a danger to themselves and hospital personnel. Commonly used medications have limitations. Our primary objective was to compare the time to a defined reduction in agitation scores for ketamine versus benzodiazepines and haloperidol, alone or in combination. Our secondary objectives were to compare rates of medication redosing, vital sign changes, and adverse events in the different treatment groups. We conducted a single-center, prospective, observational study examining agitation levels in acutely agitated emergency department patients between the ages of 18 and 65 who required sedation medication for acute agitation. Providers measured agitation levels on a previously validated 6-point sedation scale at 0-, 5-, 10-, and 15-min after receiving sedation. We also assessed the incidence of adverse events, repeat or rescue medication dosing, and changes in vital signs. 106 patients were enrolled and 98 met eligibility criteria. There was no significant difference between groups in initial agitation scores. Based on agitation scores, more patients in the ketamine group were no longer agitated than the other medication groups at 5-, 10-, and 15-min after receiving medication. Patients receiving ketamine had similar rates of redosing, changes in vital signs, and adverse events to the other groups. In highly agitated and violent emergency department patients, significantly fewer patients receiving ketamine as a first line sedating agent were agitated at 5-, 10-, and 15-min. Ketamine appears to be faster at controlling agitation than standard emergency department medications. Copyright © 2017 Elsevier Inc. All rights reserved.

State of Acute Agitation at Psychiatric Emergencies in Europe: The STAGE Study.

PubMed

San, Luis; Marksteiner, Josef; Zwanzger, Peter; Figuero, María Aragüés; Romero, Francisco Toledo; Kyropoulos, Grigorios; Peixoto, Alberto Bessa; Chirita, Roxana; Boldeanu, Anca

2016-01-01

Agitation is an array of syndromes and types of behaviors that are common in patients with psychiatric disorders. In Europe, the estimation of prevalence of agitation has been difficult due to the lack of standard studies or systematic data collection done on this syndrome. An observational, cross-sectional, multicenter study aimed to assess the prevalence of agitation episodes in psychiatric emergencies in different European countries. For 1 week, all episodes of acute agitation that were attended to at the psychiatric emergency room (ER) or Acute Inpatient Unit (AIU) in the 27 participating centers were registered. The clinical characteristics and management of the agitation episode were also described. A descriptive analysis was performed. A total of 334 agitation episodes out of 7295 psychiatric emergencies were recorded, giving a prevalence rate of 4.6% (95% CI: 4.12-5.08). Of them, 172 [9.4% (95% CI: 8.2-10.9)] were attended at the ER and 162 [2.8% (95% CI: 2.4-3.3)] at AIU. Only data from 165 episodes of agitation (those with a signed informed consent form) was registered and described in this report. The most common psychiatric conditions associated with agitation were schizophrenia, bipolar disorder and personality disorder. The management of agitation included from non-invasive to more coercive measures (mechanical, physical restraint or seclusion) that were unavoidable in more than half of the agitation episodes (59.5%). The results show that agitation is a common symptom in the clinical practice, both in emergency and inpatient psychiatric departments. Further studies are warranted to better recognize (using a standardized definition) and characterize agitation episodes.

High aeration rate enhances flow stratification in full-scale oxidation ditch.

PubMed

Diamantis, Vasileios; Papaspyrou, Ioannis; Melidis, Parasxos; Aivasidis, Alexander

2010-02-01

Aerated channel reactors with a uniform field of aeration may display flow stratification and short-circuit phenomena in wastewater treatment systems. In this study, we present data suggesting that flow stratification is closely related to the aeration rate and the arrangement of aerators. A full-scale oxidation ditch, with a total volume of 6,500 m(3) and a membrane-diffused aerated zone of 60 x 7 x 5 m (length-width-depth), was selected for water velocity measurements. Two profiles of the oxidation ditch were studied in detail: the first one was at the end of the aerated zone and the second one at the end of the anoxic zone. The results of this work demonstrate that the horizontal water velocity at the end of the aerated zone displayed significant stratification, with maximum velocity near the water surface (0.5-0.7 m/s) and almost zero velocity at a depth of 2.5 m. At the end of the anoxic zone, water velocity was uniform and equal to 0.27-0.31 m/s. Increasing the aeration rate from 1,800 to 4,300 m(3)/h, almost 90% of the water flow was found to discharge through the upper-half of the channel reactor profile. Different options to mitigate flow stratification of the oxidation ditch are discussed in this paper.

Effect of process design and operating parameters on aerobic methane oxidation in municipal WWTPs.

PubMed

Daelman, Matthijs R J; Van Eynde, Tamara; van Loosdrecht, Mark C M; Volcke, Eveline I P

2014-12-01

Methane is a potent greenhouse gas and its emission from municipal wastewater treatment plants (WWTPs) should be prevented. One way to do this is to promote the biological conversion of dissolved methane over stripping in aeration tanks. In this study, the well-established Activated Sludge Model n°1 (ASM1) and Benchmark Simulation Model n°1 (BSM1) were extended to study the influence of process design and operating parameters on biological methane oxidation. The aeration function used in BSM 1 was upgraded to more accurately describe gas-liquid transfer of oxygen and methane in aeration tanks equipped with subsurface aeration. Dissolved methane could be effectively removed in an aeration tank at an aeration rate that is in agreement with optimal effluent quality. Subsurface bubble aeration proved to be better than surface aeration, while a CSTR configuration was superior to plug flow conditions in avoiding methane emissions. The conversion of methane in the activated sludge tank benefits from higher methane concentrations in the WWTP's influent. Finally, if an activated sludge tank is aerated with methane containing off-gas, a limited amount of methane is absorbed and converted in the mixed liquor. This knowledge helps to stimulate the methane oxidizing capacity of activated sludge in order to abate methane emissions from wastewater treatment to the atmosphere. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dissolved Oxygen management in catfish ponds using electric paddlewheel aerators: new approaches with old technology

USDA-ARS?s Scientific Manuscript database

The electric paddlewheel aerator has been the main aerator used in the U.S. catfish industry for the post forty years. While it has its limitations, it is perhaps the most efficient shallow-water aerator yet to be developed. Its shortcomings result not so much from poor design, as from poor usage. U...

Application of micro bubble generator as low cost and high efficient aerator for sustainable fresh water fish farming

NASA Astrophysics Data System (ADS)

Budhijanto, Wiratni; Darlianto, Deen; Pradana, Yano Surya; Hartono, Muhamad

2017-05-01

This study aimed to apply a novel type of aerator called Micro Bubble Generator (MBG) for fresh water fish farming. The MBG was run based on the principle of venturi tube in which water was circulated through a narrowed channel so that air was sucked into the device and pushed by the flowing water to create micro-sized bubble. The MBG aerator was tested on the aquaculture of tilapia fish to be compared to conventional aerator (the bubbler currently used in aquaculture experiments) and control (container with no aeration). The population of 150 tilapia fish of the average initial length of 6.44 cm was tested in each container. The water quality parameters (COD, pH, and TAN) and fish growth parameters (length and weight) were observed for 68 days. The results highlighted the promising potential of MBG as affordable aerator to be applied in intensive aquaculture. Although the dissolved oxygen level did not differ significantly with the conventional aerator, MBG aerator indicated faster degradation of organic content in the water and induced faster growth of the fish as measured by their length and weight.

Influence of aeration during propagation of pitching yeast on fermentation and beer flavor.

PubMed

Cheong, Chul; Wackerbauer, Karl; Kang, Soon Ah

2007-02-01

The effect of yeast propagated at different aeration conditions on yeast physiology, fermentation ability, and beer quality was investigated using three strains of Saccharomyces cerevisiae. It was shown that yeast cells grown under continuous aeration conditions during propagation were almost two times higher as compared with discontinuous aeration conditions. The maximum of cell growth of all samples reached between 36 h and 48 h. The concentration of trehalose was increased under continuous aerated yeasts, whereas glycogen was decreased. It was also observed that the concentration of glycogen and trehalose in yeast cells had no direct effect on subsequent fermentation ability. The effect of yeast propagated under different aeration conditions on subsequent fermentation ability was different from yeast strains, in which the influence will be most pronounced at the first fermentation. Later, the yeasts might regain its original characteristics in the following fermentations. Generally, continuously propagated yeast had a positive effect on beer quality in subsequent fermentation. Hence, the concentration of aroma compounds obtained with yeast propagated under 6 1/h for 48 h aeration was lower than those grown under other aeration conditions in the bottom yeasts; in particular, the amounts of phenylethyl alcohol, ester, and fatty acids were decreased.

Ammonia-based feedforward and feedback aeration control in activated sludge processes.

PubMed

Rieger, Leiv; Jones, Richard M; Dold, Peter L; Bott, Charles B

2014-01-01

Aeration control at wastewater treatment plants based on ammonia as the controlled variable is applied for one of two reasons: (1) to reduce aeration costs, or (2) to reduce peaks in effluent ammonia. Aeration limitation has proven to result in significant energy savings, may reduce external carbon addition, and can improve denitrification and biological phosphorus (bio-P) performance. Ammonia control for limiting aeration has been based mainly on feedback control to constrain complete nitrification by maintaining approximately one to two milligrams of nitrogen per liter of ammonia in the effluent. Increased attention has been given to feedforward ammonia control, where aeration control is based on monitoring influent ammonia load. Typically, the intent is to anticipate the impact of sudden load changes, and thereby reduce effluent ammonia peaks. This paper evaluates the fundamentals of ammonia control with a primary focus on feedforward control concepts. A case study discussion is presented that reviews different ammonia-based control approaches. In most instances, feedback control meets the objectives for both aeration limitation and containment of effluent ammonia peaks. Feedforward control, applied specifically for switching aeration on or off in swing zones, can be beneficial when the plant encounters particularly unusual influent disturbances.

Iodine-infused aeration for hull fouling prevention: a vessel-scale study.

PubMed

Dickenson, Natasha C; Krumholz, Jason S; Hunsucker, Kelli Z; Radicone, Michael

2017-11-01

Biofouling is a significant economic and ecological problem, causing reduced vessel performance and increases in fuel consumption and emissions. Previous research has shown iodine vapor (I 2 )-infused aeration to be an environmentally friendly method for deterring the settlement of fouling organisms. An aeration system was deployed on a vessel with hull sections coated with two types of antifoulant coatings, Intersleek ® 1100 (fouling-release) and Interspeed ® BRA-640 (ablative copper biocide), as well as an inert epoxy barrier coating, to assess the effectiveness of aeration in conjunction with common marine coatings. I 2 -infused aeration resulted in consistent reductions of 80-90% in hard fouling across all three coatings. Additionally, aeration reduced the soft fouling rate by 45-70% when used in conjunction with both Intersleek ® and Interspeed ® BRA versus those coatings alone. The results of this study highlight the contribution of I 2 -infused aeration as a standalone mechanism for fouling prevention or as a complement to traditional antifouling coatings.

Effects on agitation with rivastigmine patch monotherapy and combination therapy with memantine in mild to moderate Alzheimer's disease: a multicenter 24-week prospective randomized open-label study (the Korean EXelon Patch and combination with mEmantine Comparative Trial study).

PubMed

Yoon, Soo J; Choi, Seong H; Na, Hae R; Park, Kyung-Won; Kim, Eun-Joo; Han, Hyun J; Lee, Jae-Hong; Shim, Young S; Na, Duk L

2017-03-01

Memantine is known to be effective in the treatment of the behavioral symptoms of dementia, especially agitation in moderate to severe Alzheimer's disease (AD). However, memantine and rivastigmine patch combination therapy has not been well studied in determining treatment effectiveness with mild to moderate AD patients. This was a multicenter, 24-week, prospective, randomized, open-label study design. A total 147 AD patients with Mini-Mental State Examination scores from 10 to 20 were randomly assigned to rivastigmine patch monotherapy and combination therapy with memantine groups. Agitation symptoms, using the Korean Version of the Cohen Mansfield Agitation Inventory were evaluated at baseline and at study end. Suppression and emergence of agitation symptoms were also evaluated. We carried out factor analyses to evaluate the interrelationship of agitation symptoms and to investigate treatment response in these symptoms. Factor analyses showed two symptom clusters: factor A - aggressive agitated behaviors - versus factor B - non-aggressive agitated behaviors. The rivastigmine patch monotherapy group showed significantly decreased factor B scores and had a tendency of decreased Korean Version of the Cohen Mansfield Agitation Inventory total scores and factor A scores. Conversely, the combination therapy group showed significantly increased Korean Version of the Cohen Mansfield Agitation Inventory total scores and factor B scores. Neither monotherapy nor combination therapy reduced the emergence of new agitation symptoms. In this trial of mild to moderate AD patients, the rivastigmine patch monotherapy group experienced a reduction of non-aggressive agitated behaviors. However, combination therapy with memantine did not show any benefit on the agitation associated with mild to moderate AD. Geriatr Gerontol Int 2017; 17: 494-499. © 2016 Japan Geriatrics Society.

Automated agitation management accounting for saturation dynamics.

PubMed

Rudge, A D; Chase, J G; Shaw, G M; Lee, D

2004-01-01

Agitation-sedation cycling in critically ill is damaging to patient health and increases length of and cost. A physiologically representative model of the agitation-sedation system is used as a platform to evaluate feedback controllers offering improved agitation management. A heavy-derivative controller with upper and infusion rate bounds maintains minimum plasma concentrations through a low constant infusion, and minimizes outbursts of agitation through strong, timely boluses. controller provides improved agitation management using from 37 critically ill patients, given the saturation of effect at high concentration. Approval was obtained the Canterbury Ethics Board for this research.

[Optimization and comparison of nitrogen and phosphorus removal by different aeration modes in oxidation ditch].

PubMed

Guo, Chang-Zi; Peng, Dang-Cong; Cheng, Xue-Mei; Wang, Dan

2012-03-01

The oxidation ditch operation mode was simulated by sequencing batch reactor (SBR) system with alternate stirring and aeration. The nitrogen and phosphorus removal efficiencies were investigated in two different aeration modes: point aeration and step aeration. Experimental results show that oxygen is dissolved more efficiently in point aeration mode with a longer aerobic region in the same air supply capacity, but dissolved oxygen (DO) utilization efficiency for nitrogen and phosphorus removal is high in step aeration mode. Nitrification abilities of the two modes are equal with ammonia-nitrogen (NH4(+) -N) removal efficiency of 96.68% and 97.03%, respectively. Nitrifier activities are 4.65 and 4.66 mg x (g x h)(-1) respectively. When the ratio of anoxic zones and the aerobic zones were 1, the total nitrogen (TN) removal efficiency of point aeration mode in 2, 4 or 7 partitions was respectively 60.14%, 47.93% and 33.7%. The total phosphorus (TP) removal efficiency was respectively 28.96%, 23.75% and 24.31%. The less the partitions, the higher the nitrogen and phosphorus removal efficiencies, but it is in more favor of TN removal. As for step aeration mode with only one partitioning zone, the TN and TP removal efficiencies are respectively 64.21% and 49.09%, which is better than in point aeration mode, but more conducive to the improvement of TP removal efficiency. Under the condition of sufficient nitrification in step aeration mode, the nitrogen and phosphorus removal is better with the increase of anoxic zone. The removal efficiencies of TN and TP respectively rose to 73.94% and 54.18% when the ratio of anoxic zones and the aerobic zones was increased from 1 : 1 to 1. 8 : 1. As the proportion of anoxic zones was enlarged further, nitrification and operation stability were weakened so as to affect the nitrogen and phosphorus removal efficiencies.

Low frequency aeration of pig slurry affects slurry characteristics and emissions of greenhouse gases and ammonia.

PubMed

Calvet, Salvador; Hunt, John; Misselbrook, Tom H

2017-07-01

Low frequency aeration of slurries may reduce ammonia (NH 3 ) and methane (CH 4 ) emissions without increasing nitrous oxide (N 2 O) emissions. The aim of this study was to quantify this potential reduction and to establish the underlying mechanisms. A batch experiment was designed with 6 tanks with 1 m 3 of pig slurry each. After an initial phase of 7 days when none of the tanks were aerated, a second phase of 4 weeks subjected three of the tanks to aeration (2 min every 6 h, airflow 10 m 3  h -1 ), whereas the other three tanks remained as a control. A final phase of 9 days was established with no aeration in any tank. Emissions of NH 3 , CH 4 , carbon dioxide (CO 2 ) and N 2 O were measured. In the initial phase no differences in emissions were detected, but during the second phase aeration increased NH 3 emissions by 20% with respect to the controls (8.48 vs. 7.07 g m -3  [slurry] d -1 , P < 0.05). A higher pH was found in the aerated tanks at the end of this phase (7.7 vs. 7.0 in the aerated and control tanks, respectively, P < 0.05). CH 4 emissions were 40% lower in the aerated tanks (2.04 vs. 3.39 g m -3  [slurry] d -1 , P < 0.05). These differences in NH 3 and CH 4 emissions remained after the aeration phase had finished. No effect was detected for CO 2 , and no relevant N 2 O emissions were detected during the experiment. Our results demonstrate that low frequency aeration of stored pig slurry increases slurry pH and increases NH 3 emissions.

3D-modelling of the thermal circumstances of a lake under artificial aeration

NASA Astrophysics Data System (ADS)

Tian, Xiaoqing; Pan, Huachen; Köngäs, Petrina; Horppila, Jukka

2017-12-01

A 3D-model was developed to study the effects of hypolimnetic aeration on the temperature profile of a thermally stratified Lake Vesijärvi (southern Finland). Aeration was conducted by pumping epilimnetic water through the thermocline to the hypolimnion without breaking the thermal stratification. The model used time transient equation based on Navier-Stokes equation. The model was fitted to the vertical temperature distribution and environmental parameters (wind, air temperature, and solar radiation) before the onset of aeration, and the model was used to predict the vertical temperature distribution 3 and 15 days after the onset of aeration (1 August and 22 August). The difference between the modelled and observed temperature was on average 0.6 °C. The average percentage model error was 4.0% on 1 August and 3.7% on 22 August. In the epilimnion, model accuracy depended on the difference between the observed temperature and boundary conditions. In the hypolimnion, the model residual decreased with increasing depth. On 1 August, the model predicted a homogenous temperature profile in the hypolimnion, while the observed temperature decreased moderately from the thermocline to the bottom. This was because the effect of sediment was not included in the model. On 22 August, the modelled and observed temperatures near the bottom were identical demonstrating that the heat transfer by the aerator masked the effect of sediment and that exclusion of sediment heat from the model does not cause considerable error unless very short-term effects of aeration are studied. In all, the model successfully described the effects of the aerator on the lake's temperature profile. The results confirmed the validity of the applied computational fluid dynamic in artificial aeration; based on the simulated results, the effect of aeration can be predicted.

Performance and completion assessment of an in-situ aerated municipal solid waste landfill - Final scientific documentation of an Austrian case study.

PubMed

Hrad, Marlies; Huber-Humer, Marion

2017-05-01

By converting anaerobic landfills into a biologically stabilized state through accelerating aerobic organic matter degradation, the effort and duration necessary for post-closure procedures can be shortened. In Austria, the first full-scale application of in-situ landfill aeration by means of low pressure air injection with simultaneous off-gas collection and treatment was implemented on an old MSW-landfill and operated between 2007 and 2013. Besides complementary laboratory investigations, which included waste sampling from the landfill site prior to aeration start, a comprehensive field monitoring program was conducted to assess the influence of the aeration measure on the emission behavior of the landfilled waste during the aeration period as well as after aeration completion. Although the initial waste material was described as rather stable, the lab-scale aeration tests indicated a significant improvement of the leachate quality and even the biological solid waste stability. However, the aeration success was less pronounced for the application at the landfill site, mainly due to technical limitations in the full-scale operation. In this paper main performance data of the field investigation are compared to four other scientifically documented case studies along with stability indicators for solid waste and leachate characteristics in order to evaluate the success of aeration as well as the progress of a landfill towards completion and end of post-closure care. A number of quantitative benchmarks and relevant context information for the performance assessment of the five hitherto conducted international aeration projects are proposed aiming to support the systematization and harmonization of available results from diverse field studies and full-scale applications in future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Design of high efficiency and energy saving aeration device for aquaculture

NASA Astrophysics Data System (ADS)

Liu, Sibo

2017-03-01

Energy efficient aeration device for aquaculture, in line with "by more than a generation, dynamic aeration" train of thought for technical design and improvement. Removable aeration terminal as the core, multi-level water to improve the method, the mobile fading pore aeration, intelligent mobile and open and close as the main function, aimed at solving the existing pond aeration efficiency, low energy consumption is high, the function of a single problem. From energy saving, efficiency, biological bacteria on the three directions, the aquaculture industry of energy conservation and emissions reduction. Device of the main advantages are: 1, original mobile fading aerator on the one hand, to expand the scope of work, playing a micro porous aeration of dissolved oxygen with high efficiency and to achieve "by more than a generation", on the other hand, through the sports equipment, stir the mixture of water, the water surface of photosynthesis of plants rich in dissolved oxygen input parts of the tank, compared to the stillness of the aerator can be more fully dissolved oxygen.2, through the opening of the pressure sensor indirect control device, can make the equipment timely and stop operation, convenient in use at the same time avoid the waste of energy.3, the biofilm suspension in aeration terminal, can be accomplished by nitration of microbial multi-level water improvement, still can make biofilm increase rate of netting in the movement process, the biological and mechanical aerobic promote each other, improve the efficiency of both. In addition, the device has small power consumption, low cost of characteristics. And have a certain degree of technical barriers, have their own intellectual property rights, and high degree of product market demand, easily accepted by customers, has a very high popularization value.

The substitution of sand filtration by immersed-UF for surface water treatment: pilot-scale studies.

PubMed

Lihua, Sun; Xing, Li; Guoyu, Zhang; Jie, Chen; Zhe, Xu; Guibai, Li

2009-01-01

The newly issued National Drinking Water Standard required that turbidity should be lower than 1 NTU, and the substitution of sand filtration by immersed ultrafiltration (immersed-UF) is feasible to achieve the standard. This study aimed to optimise the operational processes (i.e. aeration, backwashing) through pilot scale studies, to control membrane fouling while treating the sedimentation effluent. Results indicated that the immersed-UF was promising to treat the sedimentation effluent. The turbidity was below 0.10 NTU, bacteria and E. coli were not detected in the permeate water. The intermittent filtration with aeration is beneficial to inhibit membrane fouling. The critical aeration intensity is observed to be 60.0 m(3) m(-2) h(-1). At this aeration intensity, the decline rate of permeate flux in one period of backwashing was 1.94% and 7.03% for intermittent filtration and sustained filtration respectively. The different membrane backwashing methods (i.e. aeration 1.5 min, synchronous aeration and water backwashing 2 min, water backwashing 1.5 min; synchronous aeration and water backwashing 3 min, water backwashing 2 min; aeration 3 min, single water backwashing 2 min; synchronous aeration and water backwashing 5 min; single water backwashing 5 min) on the recovery of permeate flux were compared, indicating that the synchronous aeration and water backwashing exhibited best potential for permeate flux recovery. The optimal intensity of water backwashing is shown to be 90.0 L m(-2) h(-1). When the actual water intensity was below or exceeded the value, the recovery rate of permeate flux would be reduced. Additionally, the average operating cost for the immersed UF membrane, including the power, the chemical cleaning reagents, and membrane modules replacement, was about 0.31 RMB/m(3).

Probable reasons for expressed agitation in persons with dementia.

PubMed

Ragneskog, H; Gerdner, L A; Josefsson, K; Kihlgren, M

1998-05-01

Nursing home patients with dementia were videotaped in three previous studies. Sixty sequences of nine patients exhibiting agitated behaviors were examined to identify the most probable antecedents to agitation. Probable reasons were interpreted and applied to the Progressively Lowered Stress Threshold model, which suggests that agitation is stress related. Analysis suggests that agitation often serves as a form of communication. Two underlying reasons seem to be that the patient had loss of control over the situation and deficient autonomy. The most common causes for expressed agitation were interpreted as discomfort, a wish to be served immediately, conflict between patients or with nursing staff, reactions to environmental noises or sound, and invasion of personal space. It is recommended that nursing staff promote autonomy and independency for this group of patients whenever possible. By evaluating probable reasons for expressed agitation, the nursing staff can take steps to prevent or alleviate agitation.

Organics removal, nitrogen removal and N2O emission in subsurface wastewater infiltration systems amended with/without biochar and sludge.

PubMed

Sun, Yafei; Qi, Shiyue; Zheng, Fanping; Huang, Linli; Pan, Jing; Jiang, Yingying; Hou, Wanyuan; Xiao, Lu

2018-02-01

Organics removal, nitrogen removal, N 2 O emission and nitrogen removal functional gene abundances in four subsurface wastewater infiltration systems (SWISs), named SWIS A (no intermittent aeration without biochar and sludge), SWIS B (no intermittent aeration with biochar and sludge), SWIS C (intermittent aeration without biochar and sludge), SWIS D (intermittent aeration with biochar and sludge) were investigated. Intermittent aeration enhanced chemical oxygen demand (COD), ammonia nitrogen (NH 4 + -N), total nitrogen (TN) removal and the abundances of nitrogen removal functional genes (amoA, nxrA, napA, narG, nirS, nirK, qnorB and nosZ) compared to non-aerated SWISs. High COD (95.4 ± 0.2%), NH 4 + -N (96.2 ± 0.6%), TN (86.4 ± 0.5%) removal efficiencies and low N 2 O emission rate (18.4 mg/(m 2  d)) were obtained simultaneously in intermittent aerated SWIS amended with biochar and sludge. The results suggested that intermittent aerated SWISs amended with biochar and sludge could be an effective and appropriate method for improving treatment performance and reducing N 2 O emission. Copyright © 2017 Elsevier Ltd. All rights reserved.

Energy, cost and design aspects of coarse- and fine-bubble aeration systems in the MBBR IFAS process.

PubMed

Sander, S; Behnisch, J; Wagner, M

2017-02-01

With the MBBR IFAS (moving bed biofilm reactor integrated fixed-film activated sludge) process, the biomass required for biological wastewater treatment is either suspended or fixed on free-moving plastic carriers in the reactor. Coarse- or fine-bubble aeration systems are used in the MBBR IFAS process. In this study, the oxygen transfer efficiency (OTE) of a coarse-bubble aeration system was improved significantly by the addition of the investigated carriers, even in-process (∼1% per vol-% of added carrier material). In a fine-bubble aeration system, the carriers had little or no effect on OTE. The effect of carriers on OTE strongly depends on the properties of the aeration system, the volumetric filling rate of the carriers, the properties of the carrier media, and the reactor geometry. This study shows that the effect of carriers on OTE is less pronounced in-process compared to clean water conditions. When designing new carriers in order to improve their effect on OTE further, suppliers should take this into account. Although the energy efficiency and cost effectiveness of coarse-bubble aeration systems can be improved significantly by the addition of carriers, fine-bubble aeration systems remain the more efficient and cost-effective alternative for aeration when applying the investigated MBBR IFAS process.

Volume requirements for aerated mud drilling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, B.; Rajtar, J.M.

1995-09-01

Aerated mud drilling has been recognized as having many advantages over conventional mud drilling, such ass higher penetration rate, less formation damage, minimized lost circulation, and lower drilling cost. In some areas, the use of aerated mud as a circulating medium for drilling oil and gas wells is becoming an attractive practice. Maintaining an optimum combination of liquid and air flow rates is important in aerated drilling operations. However, most drilling operators are unclear on what constitutes the ``optimum combination of the liquid and air flow rates.`` Guo et al. presented a mathematical approach to determining the flowing bottomhole pressuremore » (BHP) for aerated mud drilling. This paper addresses the use of Guo et al.`s mathematical model to determine liquid and air volume requirements considering wellbore stability, pipe sticking, and formation damage as well as the cuttings-carry capacity of the aerated mud. For a formation-damage-prevention point of view, the liquid fraction in the fluid stream should e as low as possible. However, a sufficient mud flow rate is always required to make the hole stable and to maintain the cuttings-carrying capacity of the aerated mud without injecting much air volume. This paper provides a simple approach to determining the liquid and air volume requirements for aerated mud drilling.« less

Influence of aeration on CH4, N2O and NH3 emissions during aerobic composting of a chicken manure and high C/N waste mixture.

PubMed

Shen, Yujun; Ren, Limei; Li, Guoxue; Chen, Tongbin; Guo, Rui

2011-01-01

Co-composting of chicken manure, straw and dry grasses was investigated in a forced aeration system to estimate the effect of aeration rates on NH(3), CH(4) and N(2)O emissions and compost quality. Continuous measurements of gas emissions were carried out and detailed gas emission patterns were obtained using an intermittent-aeration of 30 min on/30 min off at rates of 0.01 (A1), 0.1 (A2) and 0.2 (A3) m(3)min(-1)m(-3). Concentrations of CH(4) and N(2)O at the low aeration rate (A1) were significantly greater than those at the other two rates, but there was no significant difference between the A2 and A3 treatments. CH(4) and N(2)O emissions for this mixture could be controlled when the composting process was aerobic and ammonia emissions were reduced at a lower aeration rate. Comparison of CH(4), N(2)O, NH(3) emissions and compost quality showed that the aeration rate of the A2 treatment was superior to the other two aeration rates. Copyright © 2010 Elsevier Ltd. All rights reserved.

Optimization of aeration for biodiesel production by Scenedesmus obliquus grown in municipal wastewater.

PubMed

Han, Song-Fang; Jin, Wenbiao; Tu, Renjie; Abomohra, Abd El-Fatah; Wang, Zhi-Han

2016-07-01

Despite the significant breakthroughs in research on microalgae as a feedstock for biodiesel, its production cost is still much higher than that of fossil diesel. One possible solution to overcome this problem is to optimize algal growth and lipid production in wastewater. The present study examines the optimization of pretreatment of municipal wastewater and aeration conditions in order to enhance the lipid productivity of Scenedesmus obliquus. Results showed that no significant differences were recorded in lipid productivity of S. obliquus grown in primary settled or sterilized municipal wastewater; however, ultrasound pretreatment of wastewater significantly decreased the lipid production. Whereas, aeration rates of 0.2 vvm significantly increased lipid content by 51 %, with respect to the non-aerated culture, which resulted in maximum lipid productivity (32.5 mg L(-1) day(-1)). Furthermore, aeration enrichment by 2 % CO2 resulted in increase of lipid productivity by 46 % over the CO2 non-enriched aerated culture. Fatty acid profile showed that optimized aeration significantly enhanced monounsaturated fatty acid production, composed mainly of C18:1, by 1.8 times over the non-aerated S. obliquus culture with insignificant changes in polyunsaturated fatty acid proportion; suggesting better biodiesel characteristics for the optimized culture.

The effect of aeration and effluent recycling on domestic wastewater treatment in a pilot-plant system of duckweed ponds.

PubMed

Ben-shalom, Miriam; Shandalov, Semion; Brenner, Asher; Oron, Gideon

2014-01-01

Three pilot-scale duckweed pond (DP) wastewater treatment systems were designed and operated to examine the effect of aeration and effluent recycling on treatment efficiency. Each system consisted of two DPs in series fed by pre-settled domestic sewage. The first system (duckweed+ conventional treatment) was 'natural' and included only duckweed plants. The second system (duckweed aeration) included aeration in the second pond. The third system (duckweed+ aeration+ circulation) included aeration in the second pond and effluent recycling from the second to the first pond. All three systems demonstrated similarly efficient removal of organic matter and nutrients. Supplemental aeration had no effect on either dissolved oxygen levels or on pollutant removal efficiencies. Although recycling had almost no influence on nutrient removal efficiencies, it had a positive impact on chemical oxygen demand and total suspended solids removals due to equalization of load and pH, which suppressed algae growth. Recycling also improved the appearance and growth rate of the duckweed plants, especially during heavy wastewater loads.

Effects of intermittent aeration periods on a structured-bed reactor continuously fed on the post-treatment of sewage anaerobic effluent.

PubMed

Silva, Bruno Garcia; Damianovic, Márcia Helena Rissato Zamariolli; Foresti, Eugenio

2018-04-20

This study assessed the simultaneous nitrification and denitrification processes and remaining organic matter removal from anaerobic reactor effluent treating wastewater in a single reactor. A structured-bed reactor, with polyurethane foam as support media, was subjected to intermittent aeration and effluent recirculation. Aerated/non-aerated periods varied in the range of 2/1-1/3 h. The chemical oxygen demand (COD) in the effluent remained between 26 and 42 mg L -1 throughout all the aeration conditions. Aeration periods of 1/2 h removed 80 and 26% of Total Kjeldahl Nitrogen and Total Nitrogen, respectively. A low solid production was observed during the 300 days of operation, resulting in a solid retention time of 139 days. The results indicate that the non-aerated periods generated alkalinity that favored nitrification, maintaining low COD concentrations in the effluent. The structured bed reactor presented a low solid production and effluent loss below 20 mgSSV L -1 , similar to concentrations obtained in secondary decanters.

Influence of aeration on volatile sulfur compounds (VSCs) and NH3 emissions during aerobic composting of kitchen waste.

PubMed

Zhang, Hongyu; Li, Guoxue; Gu, Jun; Wang, Guiqin; Li, Yangyang; Zhang, Difang

2016-12-01

This study investigates the influence of aeration on volatile sulfur compounds (VSCs) and ammonia (NH 3 ) emissions during kitchen waste composting. Aerobic composting of kitchen waste and cornstalks was conducted at a ratio of 85:15 (wet weight basis) in 60L reactors for 30days. The gas emissions were analyzed with force aeration at rates of 0.1 (A1), 0.2 (A2) and 0.3 (A3) L (kgDMmin) -1 , respectively. Results showed that VSCs emission at the low aeration rate (A1) was more significant than that at other two rates (i.e., A2 and A3 treatment), where no considerable emission difference was observed. On the other hand, NH 3 emission reduced as the aeration rate decreased. It is noteworthy that the aeration rate did not significantly affect the compost quality. These results suggest that the aeration rate of 0.2L (kgDMmin) -1 may be applied to control VSCs and NH 3 emissions during kitchen waste composting. Copyright © 2016 Elsevier Ltd. All rights reserved.

7 CFR 58.417 - Mechanical agitators.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Mechanical agitators. 58.417 Section 58.417 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....417 Mechanical agitators. The mechanical agitators shall be of sanitary construction. The carriages...

Grey-box modelling of aeration tank settling.

PubMed

Bechman, Henrik; Nielsen, Marinus K; Poulsen, Niels Kjølstad; Madsen, Henrik

2002-04-01

A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the sludge blanket depth. The model is formulated in continuous time by means of stochastic differential equations with discrete-time observations. The parameters of the model are estimated using a maximum likelihood method from data from an alternating BioDenipho waste water treatment plant (WWTP). The model is an important tool for analyzing ATS operation and for selecting the appropriate control actions during ATS, as the model can be used to predict the SS amounts in the aeration tanks as well as in the effluent from the aeration tanks.

Comparison between lab- and full-scale applications of in situ aeration of an old landfill and assessment of long-term emission development after completion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrad, Marlies; Gamperling, Oliver; Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at

Highlights: ► Current data on in situ aeration effects from the first Austrian full-scale case study. ► Data on lasting waste stabilisation after aeration completion. ► Information on the transferability of results from lab- to full-scale aeration. - Abstract: Sustainable landfilling has become a fundamental objective in many modern waste management concepts. In this context, the in situ aeration of landfills has been recognised for its potential to convert conventional anaerobic landfills into biological stabilised state, whereby both current and potential (long-term) emissions of the landfilled waste are mitigated. In recent years, different in situ aeration concepts have been successfullymore » applied in Europe, North America and Asia, all pursuing different objectives and strategies. In Austria, the first full-scale application of in situ landfill aeration by means of low pressure air injection and simultaneous off-gas collection and treatment was implemented on an old, small municipal solid waste (MSW) landfill (2.6 ha) in autumn 2007. Complementary laboratory investigations were conducted with waste samples taken from the landfill site in order to provide more information on the transferability of the results from lab- to full-scale aeration measures. In addition, long-term emission development of the stabilised waste after aeration completion was assessed in an ongoing laboratory experiment. Although the initial waste material was described as mostly stable in terms of the biological parameters gas generation potential over 21 days (GP{sub 21}) and respiration activity over 4 days (RA{sub 4}), the lab-scale experiments indicated that aeration, which led to a significant improvement of leachate quality, was accompanied by further measurable changes in the solid waste material under optimised conditions. Even 75 weeks after aeration completion the leachate, as well as gaseous emissions from the stabilised waste material, remained low and stayed below the authorised Austrian discharge limits. However, the application of in situ aeration at the investigated landfill is a factor 10 behind the lab-based predictions after 3 years of operation, mainly due to technical limitations in the full-scale operation (e.g. high air flow resistivity due to high water content of waste and temporarily high water levels within the landfill; limited efficiency of the aeration wells). In addition, material preparation (e.g. sieving, sorting and homogenisation) prior to the emplacement in Landfill Simulation Reactors (LSRs) must be considered when transferring results from lab- to full-scale application.« less

Pathways of nitrobenzene degradation in horizontal subsurface flow constructed wetlands: Effect of intermittent aeration and glucose addition.

PubMed

Kirui, Wesley K; Wu, Shubiao; Kizito, Simon; Carvalho, Pedro N; Dong, Renjie

2016-01-15

Intermittent aeration and addition of glucose were applied to horizontal subsurface flow constructed wetlands in order to investigate the effect on pathways of nitrobenzene (NB) degradation and interactions with microbial nitrogen and sulphur transformations. The experiment was carried out in three phases A, B and C consisting of different NB loading and glucose dosing. For each phase, the effect of aeration was assessed by intermittently aerating one wetland and leaving one unaerated. Regardless of whether or not the wetland was aerated, at an influent NB concentration of 140 mg/L, both wetlands significantly reduced NB to less than 2 mg/L, a reduction efficiency of 98%. However, once the influent NB concentration was increased to 280 mg/L, the aerated wetland had a higher removal performance 82% compared to that of the unaerated wetland 71%. Addition of glucose further intensified the NB removal to 95% in the aerated wetlands and 92% in the unaerated. Aeration of wetlands enhanced NB degradation, but also resulted in higher NB volatilization of 6 mg m(-2) d(-1). The detected high concentration of sulphide 20-60 mg/L in the unaerated wetland gave a strong indication that NB may act as an electron donor to sulphate-reducing bacteria, but this should be further investigated. Aeration positively improved NB removal in constructed wetlands, but resulted in higher NB volatilization. Glucose addition induced co-metabolism to enhance NB degradation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Emergence agitation during recovery from intracranial surgery under general anaesthesia: a protocol and statistical analysis plan for a prospective multicentre cohort study.

PubMed

Yan, Li-Mei; Chen, Han; Yu, Rong-Guo; Wang, Zhu-Heng; Zhou, Guan-Hua; Wang, Yong-Jin; Zhang, Xia; Xu, Ming; Chen, Lu; Zhou, Jian-Xin

2015-04-21

Emergence agitation after intracranial surgery is an important clinical issue during anaesthesia recovery. The aim of this multicentre cohort study is to investigate the incidence of emergence agitation, identify the risk factors and determine clinical outcomes in adult patients after intracranial surgery under general anaesthesia. Additionally, we will deliberately clarify the relationship between postoperative pneumocephalus and agitation. The present study is a prospective multicentre cohort study. Five intensive care units (ICUs) in China will participate in the study. Consecutive adult patients admitted to the ICUs after intracranial surgery will be enrolled. Sedation-Agitation Scale (SAS) or Richmond Agitation-Sedation Scale (RASS) will be used to evaluate the patients 12 h after the enrolment. Agitation is defined as an SAS score of 5-7, or an RASS score of +2 to +4. According to the maximal SAS and RASS score, patients will be divided into two cohorts: the agitation group and the non-agitation group. Factors potentially related to emergence agitation will be collected at study entry, during anaesthesia and operation, during postoperative care. Univariate analyses between the agitation and the non-agitation groups will be performed. The stepwise backward logistic regression will be carried out to identify the independent predictors of agitation. Patients will be followed up for 72 h after the operation. Accidental self-extubation of the endotracheal tube and removal of other catheters will be documented. The use of sedatives and analgesics will be collected. Ethics approval has been obtained from each of five participating hospitals. Study findings will be disseminated through peer-reviewed publications and conference presentations. NCT02318199. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Implementation of the Agitated Behavior Scale in the Electronic Health Record.

PubMed

Wilson, Helen John; Dasgupta, Kritis; Michael, Kathleen

The purpose of the study was to implement an Agitated Behavior Scale through an electronic health record and to evaluate the usability of the scale in a brain injury unit at a rehabilitation hospital. A quality improvement project was conducted in the brain injury unit at a large rehabilitation hospital with registered nurses as participants using convenience sampling. The project consisted of three phases and included education, implementation of the scale in the electronic health record, and administration of the survey questionnaire, which utilized the system usability scale. The Agitated Behavior Scale was found to be usable, and there was 92.2% compliance with the use of the electronic Electronic Agitated Behavior Scale. The Agitated Behavior Scale was effectively implemented in the electronic health record and was found to be usable in the assessment of agitation. Utilization of the scale through the electronic health record on a daily basis will allow for an early identification of agitation in patients with traumatic brain injury and enable prompt interventions to manage agitation.

Does Cognitive Impairment and Agitation in Dementia Influence Intervention Effectiveness? Findings From a Cluster-RCT With the Therapeutic Robot, PARO.

PubMed

Jones, Cindy; Moyle, Wendy; Murfield, Jenny; Draper, Brian; Shum, David; Beattie, Elizabeth; Thalib, Lukman

2018-04-13

To explore whether severity of cognitive impairment and agitation of older people with dementia predict outcomes in engagement, mood states, and agitation after a 10-week intervention with the robotic seal, PARO. Data from the PARO intervention-arm of a cluster-randomized controlled trial was used, which involved individual, nonfacilitated, 15-minute sessions with PARO 3 afternoons per week for 10 weeks. One hundred thirty-eight residents-aged ≥60 years, with dementia-from 9 long-term care facilities. A series of stepwise multiple linear regressions were conducted. Dependent variables were participants' levels of engagement, mood states, and agitation at week 10 [assessed by video observation and Cohen Mansfield Agitation Inventory-Short Form (CMAI-SF)]. Predictor variables were baseline levels of cognitive impairment [assessed by Rowland Universal Dementia Assessment Scale (RUDAS)] and agitation (CMAI-SF). Five models were produced. The strongest finding was that participants with more severe agitation at baseline had higher levels of agitation at week 10 (R 2  = .82, P < .001). Predictors of positive response were less significant. Low levels of agitation at baseline predicted greater positive behavioral engagement with PARO (R 2  = .054, P = .009) and fewer observed instances of agitation (R 2  = .033, P = .045) at week 10, whereas greater visual engagement was predicted by both lower levels of agitation and cognitive impairment (R 2  = .082, P = .006). Less severe cognitive impairment predicted greater pleasure at week 10 (R 2  = .067, P = .004). Participants with severe agitation had poor response to PARO. Lower levels of agitation and higher cognitive functioning were associated with better responses. In clinical practice, we recommend PARO should be restricted to people with low-moderate severity of agitation. Further research is needed to determine the optimal participant characteristics for response to PARO. Copyright © 2018 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Exploration of Near-Field Plume Properties for Aerated-Liquid Jets Using X-Ray Radiography (Postprint)

DTIC Science & Technology

2014-02-01

nozzle exit to discharge more liquid and aerating gas , plume momentum flux increases with liquid flow rate (at the same GLR) in the region...for testing. Water and nitrogen were used as the injectant and aerating gas , respectively. It was demonstrated that the liquid -weighted plume...diameter D2 = throat diameter EPL = equivalent path length GLR = aerating gas -to- liquid mass ratio I = intensity of the transmitted light I0

Effect of aerobic pre-treatment on hydrogen and methane production in a two-stage anaerobic digestion process using food waste with different compositions.

PubMed

Rafieenia, Razieh; Girotto, Francesca; Peng, Wei; Cossu, Raffaello; Pivato, Alberto; Raga, Roberto; Lavagnolo, Maria Cristina

2017-01-01

Aerobic pre-treatment was applied prior to two-stage anaerobic digestion process. Three different food wastes samples, namely carbohydrate rich, protein rich and lipid rich, were prepared as substrates. Effect of aerobic pre-treatment on hydrogen and methane production was studied. Pre-aeration of substrates showed no positive impact on hydrogen production in the first stage. All three categories of pre-aerated food wastes produced less hydrogen compared to samples without pre-aeration. In the second stage, methane production increased for aerated protein rich and carbohydrate rich samples. In addition, the lag phase for carbohydrate rich substrate was shorter for aerated samples. Aerated protein rich substrate yielded the best results among substrates for methane production, with a cumulative production of approximately 351ml/gVS. With regard to non-aerated substrates, lipid rich was the best substrate for CH 4 production (263ml/gVS). Pre-aerated P substrate was the best in terms of total energy generation which amounted to 9.64kJ/gVS. This study revealed aerobic pre-treatment to be a promising option for use in achieving enhanced substrate conversion efficiencies and CH 4 production in a two-stage AD process, particularly when the substrate contains high amounts of proteins. Copyright © 2016 Elsevier Ltd. All rights reserved.

The importance of aeration strategy in fuel alcohol fermentations contaminated with Dekkera/Brettanomyces yeasts.

PubMed

Abbott, D A; Ingledew, W M

2005-11-01

Whole corn mash fermentations infected with industrially-isolated Brettanomyces yeasts were not affected even when viable Brettanomyces yeasts out-numbered Saccharomyces yeasts tenfold at the onset of fermentation. Therefore, aeration, a parameter that is pivotal to the physiology of Dekkera/Brettanomyces yeasts, was investigated in mixed culture fermentations. Results suggest that aeration strategy plays a significant role in Dekkera/Brettanomyces-mediated inhibition of fuel alcohol fermentations. Although growth of Saccharomyces cerevisiae was not impeded, mixed culture fermentations aerated at rates of > or =20 ml air l(-1) mash min(-1) showed decreased ethanol yields and an accumulation of acetic acid. The importance of aeration was examined further in combination with organic acid(s). Growth of Saccharomyces occurred more rapidly than growth of Brettanomyces yeasts in all conditions. The combination of 0.075% (w/v) acetic acid and contamination with Brettanomyces TK 1404W did not negatively impact the final ethanol yield under fermentative conditions. Aeration, however, did prove to be detrimental to final ethanol yields. With the inclusion of aeration in the control condition (no organic acid stress) and in each fermentation containing organic acid(s), the final ethanol yields were decreased. It was therefore concluded that aeration strategy is the key parameter in regards to the negative effects observed in fuel alcohol fermentations infected with Dekkera/Brettanomyces yeasts.

Feasibility study of a passive aeration reactor equipped with vertical pipes for compost stabilization of cow manure.

PubMed

Sylla, Youssouf Boundou; Kuroda, Masao; Yamada, Masayuki; Matsumoto, Naoko

2006-10-01

Pilot-scale composting was carried out with cow manure to evaluate the performances of two passive aeration systems: a conventional passive aeration system equipped with horizontal pipes and an unusual passive aeration method based on air delivery by means of vertical pipes. The effects of both types of passive aeration apparatus were investigated in order to determine the degree of composting rate by continuously monitoring temperature, moisture content, organic matter, electrical conductivity, pH and C/N ratio in the piles. Temperatures in the range of thermophily (55-65 degrees C) were reached in all runs within 1-2 days then lasting for about 1 week, a span long enough for pathogen abatement. Results suggest that passive aeration carried out by vertical pipes is more effective for air delivery into compost piles than conventional passive aeration of air adduction with horizontal pipes. The variation in the number of vertical pipes was revealed to be an important parameter for the control of composting rate and temperature. Composting rates estimated from the heat balance equation were substantially in agreement with those computed through the conversion ratio of total organic matter decrement. The conversion ratios and composting rates obtained in this study using passive aeration with vertical pipes were well aligned with those found using forced air delivery systems.

Determination of effects of turbulence flow in a cathode environment on electricity generation using a tidal mud-based cylindrical-type sediment microbial fuel cell.

PubMed

An, Junyeong; Lee, Soo-Jin; Ng, How Yong; Chang, In Seop

2010-12-01

We examined the possibility of harvesting electricity from the surface of a tidal mud flat using a cylindrical-type sediment microbial fuel cell (SMFC), a marine mud battery (MMB), which can be applied in a sea environment where the ebb and flow occur due to tidal difference. In addition, we indirectly investigated the influence of ebb and flow in a lab, using aeration, argon gassing, and by agitating the cathodic solution. The MMBs consisted of cylindrical acrylic compartments containing a nylon membrane, an anode, and a cathode in a single body. The MMBs were stuck vertically into an artificial tidal mud flat such that the anode electrode was in direct contact with the tidal mud surface. As a result, the maximum current and power density generated were 35 mA/m(2) and 9 mW/m(2), respectively, thus verifying that it is possible to harvest electricity from the surface of a tidal mud flat using an MMB without burying the anode electrode in the tidal mud. Furthermore, the results of tests using an artificial turbulence flow showed the flow induced by the tidal ebb and flow could allow the performance of MMBs to be enhanced. Copyright © 2010 Elsevier Ltd. All rights reserved.

Realm of Thermoalkaline Lipases in Bioprocess Commodities.

PubMed

Lajis, Ahmad Firdaus B

2018-01-01

For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network), and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT), and aeration rate). Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization) are also highlighted in this article.

Plant cell cultures: bioreactors for industrial production.

PubMed

Ruffoni, Barbara; Pistelli, Laura; Bertoli, Alessandra; Pistelli, Luisa

2010-01-01

The recent biotechnology boom has triggered increased interest in plant cell cultures, since a number of firms and academic institutions investigated intensively to rise the production of very promising bioactive compounds. In alternative to wild collection or plant cultivation, the production of useful and valuable secondary metabolites in large bioreactors is an attractive proposal; it should contribute significantly to future attempts to preserve global biodiversity and alleviate associated ecological problems. The advantages of such processes include the controlled production according to demand and a reduced man work requirement. Plant cells have been grown in different shape bioreactors, however, there are a variety of problems to be solved before this technology can be adopted on a wide scale for the production of useful plant secondary metabolites. There are different factors affecting the culture growth and secondary metabolite production in bioreactors: the gaseous atmosphere, oxygen supply and CO2 exchange, pH, minerals, carbohydrates, growth regulators, the liquid medium rheology and cell density. Moreover agitation systems and sterilization conditions may negatively influence the whole process. Many types ofbioreactors have been successfully used for cultivating transformed root cultures, depending on both different aeration system and nutrient supply. Several examples of medicinal and aromatic plant cultures were here summarized for the scale up cultivation in bioreactors.

Production of Fumaric Acid in 20-Liter Fermentors

PubMed Central

Rhodes, R. A.; Lagoda, A. A.; Misenheimer, T. J.; Smith, M. L.; Anderson, R. F.; Jackson, R. W.

1962-01-01

The conditions necessary for the production of fumaric acid in 20-liter fermentors by fermentation of glucose with Rhizopus arrhizus strain NRRL 2582 were determined. Continuous neutralization of fumaric acid was necessary for optimal yields. Yields of the calcium salt were in excess of 65 g of fumaric acid from 100 g of sugar consumed during fermentation of sugar concentrations of 10 to 16%. Conditions established for calcium fumarate production include a simple mineral salts medium, 0.5 v:v:min aeration rate, 300 rev/min agitation rate in a baffled tank, 33 C incubation temperature, CaCO3 to neutralize the acid formed, and a 4 to 5% (v/v) vegetative inoculum. A suitable procedure and medium for the preparation of a vigorous vegetative inoculum were established. The tendency for calcium fumarate fermentations to foam excessively was controlled with a proper antifoam agent added prior to sterilization of the medium and again at daily intervals during fermentation. The production of soluble sodium or potassium fumarates was inhibited when the concentration of fumarates reached 3.5 to 4.0%. No means of overcoming this inhibition was found. Starches and certain other grain-derived carbohydrates were fermented to form calcium fumarate in flask experiments with approximately the same efficiency as was glucose. PMID:16349614

Two-Step Production of Phenylpyruvic Acid from L-Phenylalanine by Growing and Resting Cells of Engineered Escherichia coli: Process Optimization and Kinetics Modeling

PubMed Central

Hou, Ying; Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-dong; Liu, Long; Du, Guocheng; Chen, Jian

2016-01-01

Phenylpyruvic acid (PPA) is widely used in the pharmaceutical, food, and chemical industries. Here, a two-step bioconversion process, involving growing and resting cells, was established to produce PPA from l-phenylalanine using the engineered Escherichia coli constructed previously. First, the biotransformation conditions for growing cells were optimized (l-phenylalanine concentration 20.0 g·L−1, temperature 35°C) and a two-stage temperature control strategy (keep 20°C for 12 h and increase the temperature to 35°C until the end of biotransformation) was performed. The biotransformation conditions for resting cells were then optimized in 3-L bioreactor and the optimized conditions were as follows: agitation speed 500 rpm, aeration rate 1.5 vvm, and l-phenylalanine concentration 30 g·L−1. The total maximal production (mass conversion rate) reached 29.8 ± 2.1 g·L−1 (99.3%) and 75.1 ± 2.5 g·L−1 (93.9%) in the flask and 3-L bioreactor, respectively. Finally, a kinetic model was established, and it was revealed that the substrate and product inhibition were the main limiting factors for resting cell biotransformation. PMID:27851793

Swainsonine, a novel fungal metabolite: optimization of fermentative production and bioreactor operations using evolutionary programming.

PubMed

Singh, Digar; Kaur, Gurvinder

2014-08-01

The optimization of bioreactor operations towards swainsonine production was performed using an artificial neural network coupled evolutionary program (EP)-based optimization algorithm fitted with experimental one-factor-at-a-time (OFAT) results. The effects of varying agitation (300-500 rpm) and aeration (0.5-2.0 vvm) rates for different incubation hours (72-108 h) were evaluated in bench top bioreactor. Prominent scale-up parameters, gassed power per unit volume (P g/V L, W/m(3)) and volumetric oxygen mass transfer coefficient (K L a, s(-1)) were correlated with optimized conditions. A maximum of 6.59 ± 0.10 μg/mL of swainsonine production was observed at 400 rpm-1.5 vvm at 84 h in OFAT experiments with corresponding P g/VL and K L a values of 91.66 W/m(3) and 341.48 × 10(-4) s(-1), respectively. The EP optimization algorithm predicted a maximum of 10.08 μg/mL of swainsonine at 325.47 rpm, 1.99 vvm and 80.75 h against the experimental production of 7.93 ± 0.52 μg/mL at constant K L a (349.25 × 10(-4) s(-1)) and significantly reduced P g/V L (33.33 W/m(3)) drawn by the impellers.

Dissolved oxygen control strategy for improvement of TL1-1 production in submerged fermentation by Daldinia eschscholzii.

PubMed

Wei, Xing-Chen; Tang, Liu; Lu, Yan-Hua

2017-01-01

2,3-Dihydro-5-hydroxy-2-methylchromen-4-one (TL1-1) is a phenolic compound with significant anti-fungal and anti-cancer activities produced by Daldinia eschscholzii ( D. eschscholzii ). However, studies have rarely been reported on the fermentation process of D. eschscholzii due to the urgent demand for its pharmaceutical researches and applications. In this work, the optimal fermentation medium for improved TL1-1 yield was first obtained in a shake flask. As the fermentation process was scaling up, the marked effects of dissolved oxygen (DO) on cell growth and TL1-1 biosynthesis were observed and confirmed. Controlling a suitable DO level by the adjustment of agitation speed and aeration rate remarkably enhanced TL1-1 production in a lab-scale bioreactor. Moreover, the fermentation of D. eschscholzii was successfully applied in 500-L bioreactor, and TL1-1 production has achieved 873.63 mg/L, approximately 15.4-fold than its initial production (53.27 mg/L). Dissolved oxygen control strategy for enhancing TL1-1 production was first proposed. Furthermore, control of the appropriate DO level has successfully performed for improving TL1-1 yield and scale-up of D. eschscholzii fermentation process.

40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid or...

40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid or...

40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid or...

40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

Code of Federal Regulations, 2012 CFR

2012-07-01

..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid or...

40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid or...

40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid service...

Aeration of the teuftal landfill: Field scale concept and lab scale simulation.

PubMed

Ritzkowski, Marco; Walker, Beat; Kuchta, Kerstin; Raga, Roberto; Stegmann, Rainer

2016-09-01

Long lasting post-closure care (PCC) is often the major financial burden for operators of municipal solid waste (MSW) landfills. Beside costs for the installation and maintenance of technical equipment and barriers, in particular long term treatment of leachate and landfill gas has to be paid from capital surplus. Estimations based on laboratory experiments project time periods of many decades until leachate quality allows for direct discharge (i.e. no need for further purification). Projections based on leachate samples derived from the last 37years for 35 German landfills confirm these assumption. Moreover, the data illustrate that in particular ammonium nitrogen concentrations are likely to fall below limit values only after a period of 300years. In order to avoid long lasting PCC the operator of Teuftal landfill, located in the Swiss canton Bern, decided to biologically stabilize the landfill by means of a combined in situ aeration and moisturization approach. In December 2014 the aeration started at a landfill section containing approximately 30% of the total landfill volume. From summer 2016 onwards the remaining part of the landfill will be aerated. Landfill aeration through horizontal gas and leachate drains is carried out for the first time in field scale in Europe. The technical concept is described in the paper. Parallel to field scale aeration, investigations for the carbon and nitrogen turnover are carried out by means of both simulated aerated landfills and simulated anaerobic landfills. The results presented in this paper demonstrate that aeration is capable to enhance, both carbon mobilization and discharge via the gas phase. This effect comes along with a significant increase in bio-stabilization of the waste organic fraction, which positively affects the landfill emission behavior in the long run. In terms of leachate pollution reduction it could be demonstrated that the organic load decrease fast and widely independent of the adjusted aeration rates whereby ammonium nitrogen load efficiently decrease later and only under higher aeration rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nitrogen removal from wastewater by an aerated subsurface-flow constructed wetland in cold climates.

PubMed

Redmond, Eric D; Just, Craig L; Parkin, Gene F

2014-04-01

The objective of this study was to assess the role of cyclic aeration, vegetation, and temperature on nitrogen removal by subsurface-flow engineered wetlands. Aeration was shown to enhance total nitrogen and ammonia removal and to enhance removal of carbonaceous biochemical oxygen demand, chemical oxygen demand, and phosphorus. Effluent ammonia and total nitrogen concentrations were significantly lower in aerated wetland cells when compared with unaerated cells. There was no significant difference in nitrogen removal between planted and unplanted cells. Effluent total nitrogen concentrations ranged from 9 to 12 mg N/L in the aerated cells and from 23 to 24 mg N/L in unaerated cells. Effluent ammonia concentrations ranged from 3 to 7 mg N/L in aerated wetland cells and from 22 to 23 mg N/L in unaerated cells. For the conditions tested, temperature had only a minimal effect on effluent ammonia or total nitrogen concentrations. The tanks-in-series and the PkC models predicted the general trends in effluent ammonia and total nitrogen concentrations, but did not do well predicting short-term variability. Rate coefficients for aerated systems were 2 to 10 times greater than those for unaerated systems.

Enhanced organics and nitrogen removal in batch-operated vertical flow constructed wetlands by combination of intermittent aeration and step feeding strategy.

PubMed

Fan, Jinlin; Liang, Shuang; Zhang, Bo; Zhang, Jian

2013-04-01

Oxygen and carbon source supply are usually insufficient in subsurface flow constructed wetlands. Simultaneous removal of organic pollutants and nitrogen in five batch-operated vertical flow constructed wetlands under different operating conditions was investigated. Alternate aerobic and anaerobic regions were created well with intermittent aeration. Four-month experiments showed that the wetland-applied intermittent aeration combined with step feeding strategy (reactor E) greatly improved the removal of organics, ammonium nitrogen (NH4-N), and total nitrogen (TN) simultaneously, which were 97, 96, and 82%, respectively. It was much better than non-aerated reactors A and B and outperformed intermittently aerated reactor D without step feeding. Continuous aeration (reactor C) significantly enhanced the organics removal and nitrification, but it limited the TN removal (29%) seriously as a result of low denitrification level, and the high operation cost remained a question. The effect of plants was confirmed in this study, and the monitoring data showed that the plants could grow normally. Intermittent aeration as well as step feeding had no obvious influence on the growth of wetland plants in this study.

Accelerated anaerobic hydrolysis rates under a combination of intermittent aeration and anaerobic conditions.

PubMed

Jensen, T R; Lastra Milone, T; Petersen, G; Andersen, H R

2017-04-01

Anaerobic hydrolysis in activated return sludge was investigated in laboratory scale experiments to find if intermittent aeration would accelerate anaerobic hydrolysis rates compared to anaerobic hydrolysis rates under strict anaerobic conditions. The intermittent reactors were set up in a 240 h experiment with intermittent aeration (3 h:3 h) in a period of 24 h followed by a subsequent anaerobic period of 24 h in a cycle of 48 h which was repeated five times during the experiment. The anaerobic reactors were kept under strict anaerobic conditions in the same period (240 h). Two methods for calculating hydrolysis rates based on soluble chemical oxygen demand were compared. Two-way analysis of variance with the Bonferroni post-test was performed in order to register any significant difference between reactors with intermittent aeration and strictly anaerobic conditions respectively. The experiment demonstrated a statistically significant difference in favor of the reactors with intermittent aeration showing a tendency towards accelerated anaerobic hydrolysis rates due to application of intermittent aeration. The conclusion of the work is thus that intermittent aeration applied in the activated return sludge process can improve the treatment capacity further in full scale applications.

Lawson Aerator applications on rangelands

USDA-ARS?s Scientific Manuscript database

Rangeland drills, brush hogs, Dixie harrows, tandem discs and other equipment have played an important role in treating degraded rangeland environments. The Lawson Aerator is one of the newer implements to enter the scene for rangeland improvements. The Lawson Aerator was designed as a pasture renov...

Optimization of micro-aeration intensity in acidogenic reactor of a two-phase anaerobic digester treating food waste.

PubMed

Xu, Suyun; Selvam, Ammaiyappan; Wong, Jonathan W C

2014-02-01

Micro-aeration is known to promote the activities of hydrolytic exo-enzymes and used as a strategy to improve the hydrolysis of particulate substrate. The effect of different micro-aeration rates, 0, 129, 258, and 387 L-air/kg TS/d (denoted as LBR-AN, LBR-6h, LBR-3h and LBR-2h, respectively) on the solubilization of food waste was evaluated at 35°C in four leach bed reactors (LBR) coupled with methanogenic upflow anaerobic sludge blanket (UASB) reactor. Results indicate that the intensity of micro-aeration influenced the hydrolysis and methane yield. Adequate micro-aeration intensity in LBR-3h and LBR-2h significantly enhanced the carbohydrate and protein hydrolysis by 21-27% and 38-64% respectively. Due to the accelerated acidogenesis, more than 3-fold of acetic acid and butyric acid were produced in LBR-3h as compared to the anaerobic treatment LBR-AN resulting in the maximum methane yield of 0.27 L CH4/g VS(added) in the UASB. The performance of LBR-6h with inadequate aeration was similar to that of LBR-AN with a comparable hydrolysis degree. Nevertheless, higher aeration intensity in LBR-2h was also unfavorable for methane yield due to significant biomass generation and CO2 respiration of up to 18.5% and 32.8% of the total soluble hydrolysate, respectively. To conclude, appropriate micro-aeration rate can promote the hydrolysis of solid organic waste and methane yield without undesirable carbon loss and an aeration intensity of 258 L-air/kg TS/d is recommended for acidogenic LBR treating food waste. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of caffeine on mitotic index, mitotic aberrations and bimitosis with and without aeration.

PubMed

Röper, W

1977-07-01

The effects of 1 to 3 h 0.2% caffeine treatment on mitosis in lateral roots of Vicia faba with and without aeration have been investigated. During the treatment a marked decrease of the mitotic index followed by strong deviations and changing phase indices can be stated. By means of aeration the number of mitotic aberrations increases with time of treatment, while it decreases without aeration until 3 h treatment. Tetraploid cells are supposed to be formed by spindle aberrations at early anaphase. The number of binucleate and tetraploid cells is affected by aeration during caffeine treatment. During division of the binucleate cells tetraploid nuclei are formed by fusions, so the population of binucleate cells may become smaller.

Nurse education regarding agitated patients and its effects on clinical practice.

PubMed

Ozdemir, Leyla; Karabulut, Erdem

This study identified the impact of an education program on nurses' practices for agitated patients and documented the changes in practice after completion of the training. Eighteen cardiac intensive care nurses were included to the study. Prior to nurses' participation in an education program, a pre-test indicating nurses' current practices for 40 agitated patients was evaluated with the 'Nurse Practice Form'. After the pre-test data collection period was completed, the 2-day training program on caring for agitated patients was conducted. The last step of the study was evaluation of post-test nurses' practices for 40 agitated patients using the 'Nurse Practice Form'. The findings indicated that instead of pre-test nurses' use of physical restraints for controlling agitated patients without a physician order, none of post-test nurses applied them. The training program provided nurses the knowledge and skills needed to evaluate and to manage the causes of agitation.

Detecting agitation and aggression in people with dementia using sensors-A systematic review.

PubMed

Khan, Shehroz S; Ye, Bing; Taati, Babak; Mihailidis, Alex

2018-06-01

Agitation and aggression are among the most challenging symptoms of dementia. Agitated persons with dementia can harm themselves, their caregivers, or other patients in a care facility. Automatic detection of agitation would be useful to alert caregivers so that appropriate interventions can be performed. The building blocks in the automatic detection of agitation and aggression are appropriate sensing platforms and generalized predictive models. In this article, we perform a systematic review of studies that use different types of sensors to detect agitation and aggression in persons with dementia. We conclude that actigraphy shows some evidence of correlation with incidences of agitation and aggression; however, multimodal sensing has not been fully evaluated for this purpose. Based on this systematic review, we provide guidelines and recommendations for future research directions in this field. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Amlodipine and the Successful Management of Post-Electroconvulsive Therapy Agitation.

PubMed

Shahriari, Ali; Khooshideh, Maryam; Sheikh, Mahdi

2016-01-01

Electroconvulsive therapy (ECT) is a highly effective nonpharmacologic treatment for the management of depression and some other psychiatric disorders. Post-ECT agitation occurs in up to 12% of ECT treatments and is characterized by motor restlessness, irritability, disorientation, and panic-like behaviors. The severity of post-ECT agitation ranges from mild and self-limited to serious and severe forms requiring prompt medical intervention to protect the patient and the medical staff. In severe agitation medical management may be necessary which consists of using sedative agents, either benzodiazepines or propofol. The side-effects of these sedative agents, especially in the elderly population, necessitate finding ways that could help the prevention of the occurrence of agitation after ECT treatments. We report a 68-year-old female with major depression who was referred for ECT. She experienced severe post-ECT agitation requiring medical intervention after all ECT treatments. Administering of oral amlodipine (5 mg) one hour before ECT treatment successfully prevented the occurrence of post-ECT agitation in this patient. We briefly discuss the possible underlying mechanisms and pathophysiology of amlodipine in the prevention of post-ECT agitation.

FOULING OF FINE PORE DIFFUSED AERATORS: AN INTER- PLANT COMPARISON

EPA Science Inventory

There has been increasing interest in fine pore aeration systems, along with concerned about diffuser fouling and the subsequent loss of aeration efficiency. The objective of this study was to assess the relative fouling tendency of fine bubble diffusers t nine activated sludge ...

Aerated biofilters with multiple-level air injection configurations to enhance biological treatment of methane emissions.

PubMed

Farrokhzadeh, Hasti; Hettiaratchi, J Patrick A; Jayasinghe, Poornima; Kumar, Sunil

2017-09-01

Aiming to improve conventional methane biofilter performance, a multiple-level aeration biofilter design is proposed. Laboratory flow-through column experiments were conducted to evaluate three actively-aerated methane biofilter configurations. Columns were aerated at one, two, and three levels of the bed depth, with air introduced at flow rates calculated from methane oxidation reaction stoichiometry. Inlet methane loading rates were increased in five stages between 6 and 18mL/min. The effects of methane feeding rate, levels of aeration, and residence time on methane oxidation rates were determined. Samples collected after completion of flow-through experiments were used to determine methane oxidation kinetic parameters, V max , K m , and methanotrophic community distribution across biofilter columns. Results obtained from mixed variances analysis and response surfaces, as well as methanotrophic activity data, suggested that, biofilter column with two aeration levels has the most even performance over time, maintaining 85.1% average oxidation efficiency over 95days of experiments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Achieving ethanol-type fermentation for hydrogen production in a granular sludge system by aeration.

PubMed

Zhang, Song; Liu, Min; Chen, Ying; Pan, Yu-Ting

2017-01-01

To investigate the effects of aeration on hydrogen-producing granular system, experiments were performed in two laboratory-scale anaerobic internal circulation hydrogen production (AICHP) reactors. The preliminary experiment of Reactor 1 showed that direct aeration was beneficial to enhancing hydrogen production. After the direct aeration was implied in Reactor 2, hydrogen production rate (HPR) and hydrogen content were increased by 100% and 60%, respectively. In addition, mixed-acid fermentation was transformed into typical ethanol-type fermentation (ETF). Illumina MiSeq sequencing shows that the direct aeration did not change the species of hydrogen-producing bacteria but altered their abundance. Hydrogen-producing bacteria and ethanol-type fermentative bacteria were increased by 24.5% and 146.3%, respectively. Ethanoligenens sp. sharply increased by 162.2% and turned into predominant bacteria in the system. These findings indicated that appropriate direct aeration might be a novel and promising way to obtain ETF and enhance hydrogen production in practical use. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Effects of a Single Session of Music Therapy on the Agitated Behaviors of Patients Receiving Hospice Care.

PubMed

Cadwalader, Alyssa; Orellano, Shashanna; Tanguay, Carla; Roshan, Ramesh

2016-08-01

Research suggests that agitation is a common symptom for hospice patients, but while studies have examined the outcomes of music therapy on the agitated behaviors of patients in other settings, none have addressed this symptom in patients with terminal illnesses. The study objective was to determine whether a single session of music therapy provided by a board certified music therapist and using the entrainment principle would decrease agitation in hospice patients. This pilot study was a single-blind, pretest/posttest design. Music therapists used the principle of entrainment with live music during the treatment session. Subjects included in the study were 77 patients at a large hospice in south Florida with documented agitation. Agitation was measured using the Overt Agitation Severity Scale (OASS) for 5 minutes prior to and 5 minutes following a 20 minute music therapy intervention. Results from 73 participants were analyzed with a mean difference of -5.77 points from pretest to posttest. Results indicating a decrease in agitation were statistically significant (p < 0.001) for the entire sample. Age, gender, location, and diagnosis were found to have no significant effects on the results. Results indicate that a single session of music therapy using the entrainment principle may be an effective treatment for hospice patients experiencing agitation.

The relationship between agitation and impairments of orientation and memory during the PTA period after traumatic brain injury.

PubMed

McKay, Adam; Love, Jasmine; Trevena-Peters, Jessica; Gracey, Jacinta; Ponsford, Jennie

2018-06-03

Agitation is common during the post-traumatic amnesia (PTA) period after traumatic brain injury (TBI), although our knowledge of what causes or predicts agitation is limited. The current study aimed to examine the association of agitation in PTA with the concurrent impairments in orientation and memory while controlling for covariates of agitation. Participants were 125 patients in PTA following moderate to extremely severe TBI recruited from an inpatient brain injury rehabilitation service who were assessed throughout PTA on the Agitated Behavior Scale (ABS) and the Westmead PTA Scale (WPTAS). Agitation was observed in 42.4% of participants (ABS score > 21), with disinhibited behaviours (e.g., distractibility and impulsivity) most common. Multilevel modelling found daily ABS scores to be associated with daily scores on the WPTAS but in a non-linear pattern. Analysis of covariates found that shorter time post-admission, younger age, presence of infection and higher antipsychotic doses were associated with higher ABS scores. These results support a relationship between agitation and the concurrent cognitive impairment during PTA. While a causal link cannot yet be inferred, management strategies that can potentially interfere with cognition (e.g., sedating medications, environmental changes) should be used cautiously in case they exacerbate agitation.

Risk factors for agitation in critically ill patients

PubMed Central

de Almeida, Thiago Miranda Lopes; de Azevedo, Luciano Cesar Pontes; Nosé, Paulo Maurício Garcia; de Freitas, Flavio Geraldo Resende; Machado, Flávia Ribeiro

2016-01-01

Objective To evaluate the incidence of agitation in the first 7 days after intensive care unit admission, its risk factors and its associations with clinical outcomes. Methods This single-center prospective cohort study included all patients older than 18 years with a predicted stay > 48 hours within the first 24 hours of intensive care unit admission. Agitation was defined as a Richmond Agitation Sedation Scale score ≥ +2, an episode of agitation or the use of a specific medication recorded in patient charts. Results Agitation occurred in 31.8% of the 113 patients. Multivariate analysis showed that delirium [OR = 24.14; CI95% 5.15 - 113.14; p < 0.001], moderate or severe pain [OR = 5.74; CI95% 1.73 - 19.10; p = 0.004], mechanical ventilation [OR = 10.14; CI95% 2.93 - 35.10; p < 0.001], and smoking habits [OR = 4.49; CI95% 1.33 - 15.17; p = 0.015] were independent factors for agitation, while hyperlactatemia was associated with a lower risk [OR = 0.169; CI95% 0.04 - 0.77; p = 0.021]. Agitated patients had fewer mechanical ventilation-free days at day 7 (p = 0.003). Conclusion The incidence of agitation in the first 7 days after admission to the intensive care unit was high. Delirium, moderate/severe pain, mechanical ventilation, and smoking habits were independent risk factors. Agitated patients had fewer ventilator-free days in the first 7 days. PMID:28099638

Reducing aeration energy consumption in a large-scale membrane bioreactor: Process simulation and engineering application.

PubMed

Sun, Jianyu; Liang, Peng; Yan, Xiaoxu; Zuo, Kuichang; Xiao, Kang; Xia, Junlin; Qiu, Yong; Wu, Qing; Wu, Shijia; Huang, Xia; Qi, Meng; Wen, Xianghua

2016-04-15

Reducing the energy consumption of membrane bioreactors (MBRs) is highly important for their wider application in wastewater treatment engineering. Of particular significance is reducing aeration in aerobic tanks to reduce the overall energy consumption. This study proposed an in situ ammonia-N-based feedback control strategy for aeration in aerobic tanks; this was tested via model simulation and through a large-scale (50,000 m(3)/d) engineering application. A full-scale MBR model was developed based on the activated sludge model (ASM) and was calibrated to the actual MBR. The aeration control strategy took the form of a two-step cascaded proportion-integration (PI) feedback algorithm. Algorithmic parameters were optimized via model simulation. The strategy achieved real-time adjustment of aeration amounts based on feedback from effluent quality (i.e., ammonia-N). The effectiveness of the strategy was evaluated through both the model platform and the full-scale engineering application. In the former, the aeration flow rate was reduced by 15-20%. In the engineering application, the aeration flow rate was reduced by 20%, and overall specific energy consumption correspondingly reduced by 4% to 0.45 kWh/m(3)-effluent, using the present practice of regulating the angle of guide vanes of fixed-frequency blowers. Potential energy savings are expected to be higher for MBRs with variable-frequency blowers. This study indicated that the ammonia-N-based aeration control strategy holds promise for application in full-scale MBRs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of aeration on matrix temperature by infrared thermal imager and computational fluid dynamics during sludge bio-drying.

PubMed

Yu, Dawei; Yang, Min; Qi, Lu; Liu, Mengmeng; Wang, Yawei; Wei, Yuansong

2017-10-01

The effect of aeration on the pile matrix temperature was investigated using thermocouples and Infrared Thermal Imager (IRI) for temperature sensing, and Computational Fluid Dynamics (CFD) for modelling of temperature variation during aeration in a full-scale sludge biodrying plant. With aeration saving of 20%, the improved strategy speeded up biodrying from 21 days to 14 days, while achieving similar drying effect. A persistent thermocouple recorded the one-dimensional (1D) total temperature variation of all aeration strategies. The IRI captured the rapid two-dimensional (2D) pile temperature dropped from 72.5 °C to 30.3 °C during 6 min of aeration, which mechanism suggested as the latent heat of moisture evaporation and sensible heat of air exchange. The CFD three-dimensional (3D) CFD results highlight the importance of latent heat rather than sensible heat. Therefore, the pile temperature drop inferred is ΔT = 5.38 °C theoretically and ΔT = 5.17 ± 4.56 °C practically, per unit of MC removed. These findings also emphasize the possibility of a pile temperature valley, due to excessive aeration under unsaturated vapour conditions. Surface temperature monitored by IRI coupled with 3D temperature simulated by CFD rapidly gives a clear matrix temperature evolution, empowering biodrying by more accurate temperature and aeration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Luffa sponge offsets the negative effects of aeration on bacterial cellulose production.

PubMed

Krusong, W; Kerdpiboon, S; Pornpukdeewattana, S; Jindaprasert, A

2016-12-01

To offset the negative effects of aeration on bacterial cellulose (BC) production by acetic acid bacteria using enmeshed cellulose microfibrils (CM) on luffa sponge matrices (LSM). The CM were enmeshed on LSM (LSM-CM). The optimal amount of LSM-CM was determined for BC production under aerated conditions. Without LSM-CM, no BC was produced in seven out of nine production cycles at the highest aeration rate (9 l min -1 ). However, with 0·5% LSM-CM and an aeration rate of 3 l min -1 , a satisfactory oxygen transfer coefficient was achieved, and also a good yield of BC (5·24 g l -1 ). Moreover, the LSM-CM was able to be recycled through nine consecutive BC production cycles. The highest BC yields (from 5·8 ± 0·4 to 6·6 ± 0·4 g l -1 ) were associated with high bacterial biomass and this was confirmed by scanning electron microscopy. We confirm that LSM-CM works well as a starter. Microenvironments low in dissolved oxygen within the matrices of LSM-CM are important for BC production under aeration conditions. The LSM-CM provides a microenvironment which offsets the negative effects of aeration on BC production. A sustainable, economic process for mass BC production is described using recycled LSM-CM with aeration. © 2016 The Society for Applied Microbiology.

Pilot plant demonstration of stable and efficient high rate biological nutrient removal with low dissolved oxygen conditions.

PubMed

Keene, Natalie A; Reusser, Steve R; Scarborough, Matthew J; Grooms, Alan L; Seib, Matt; Santo Domingo, Jorge; Noguera, Daniel R

2017-09-15

Aeration in biological nutrient removal (BNR) processes accounts for nearly half of the total electricity costs at many wastewater treatment plants. Even though conventional BNR processes are usually operated to have aerated zones with high dissolved oxygen (DO) concentrations, recent research has shown that nitrification can be maintained using very low-DO concentrations (e.g., below 0.2 mg O 2 /L), and therefore, it may be possible to reduce energy use and costs in BNR facilities by decreasing aeration. However, the effect of reduced aeration on enhanced biological phosphorus removal (EBPR) is not understood. In this study, we investigated, at the pilot-scale level, the effect of using minimal aeration on the performance of an EBPR process. Over a 16-month operational period, we performed stepwise decreases in aeration, reaching an average DO concentration of 0.33 mg O 2 /L with stable operation and nearly 90% phosphorus removal. Under these low-DO conditions, nitrification efficiency was maintained, and nearly 70% of the nitrogen was denitrified, without the need for internal recycling of high nitrate aeration basin effluent to the anoxic zone. At the lowest DO conditions used, we estimate a 25% reduction in energy use for aeration compared to conventional BNR operation. Our improved understanding of the efficiency of low-DO BNR contributes to the global goal of reducing energy consumption during wastewater treatment operations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aerated Shewanella oneidensis in Continuously-fed Bioelectrochemical Systems for Power and Hydrogen Production

USDA-ARS?s Scientific Manuscript database

We studied the effects of aeration of Shewanella oneidensis on potentiostatic current production, iron(III) reduction, hydrogen production in a microbial electrolysis cell, and electric power generation in a microbial fuel cell. The potentiostatic performance of aerated S. oneidensis was considerab...

OXIDATION OF AS(III) BY AERATION AND STORAGE

EPA Science Inventory

A study of the effects of aeration and storage on the oxidation of arsenic(III) was undertaken at three utilities in the US to establish the engineering significance of aeration as a potential pre-treatment method for arsenic removal. The results of this study clearly establish t...

LEACHING OF URANIUM ORES USING ALKALINE CARBONATES AND BICARBONATES AT ATMOSPHERIC PRESSURE

DOEpatents

Thunaes, A.; Brown, E.A.; Rabbits, A.T.; Simard, R.; Herbst, H.J.

1961-07-18

A method of leaching uranium ores containing sulfides is described. The method consists of adding a leach solution containing alkaline carbonate and alkaline bicarbonate to the ore to form a slurry, passing the slurry through a series of agitators, passing an oxygen containing gas through the slurry in the last agitator in the series, passing the same gas enriched with carbon dioxide formed by the decomposition of bicarbonates in the slurry through the penultimate agitator and in the same manner passing the same gas increasingly enriched with carbon dioxide through the other agitators in the series. The conditions of agitation is such that the extraction of the uranium content will be substantially complete before the slurry reaches the last agitator.

Low gravity reorientation in a scale-model Centaur liquid-hydrogen tank

NASA Technical Reports Server (NTRS)

Salzman, J. A.; Masica, W. J.; Lacovic, R. F.

1973-01-01

An experiment was conducted to investigate the process of liquid reorientation from one end of a scale-model Centaur liquid-hydrogen tank to the other end by means of low-level accelerations. Prior to reorientation, the liquid was stabilized at the top of the tank at a Bond number of 15. Tanks both with and without ring baffles and with tank radii of 5.5 and 7.0 centimeters were used in the study. Reorientation acceleration values were varied to obtain Bond numbers of 200 and 450. Liquid fill levels of 20 and 70 percent were used. From the data in this study, relations were developed to estimate reorientation event times in unbaffled tanks through the point of final liquid clearing from the top of the tank. The insertion of ring baffles drastically changed the reorientation flow profiles but resulted in only minor differences in the times of tank-top uncovering and liquid collection.

Investigation of the effects of inlet shapes on fan noise radiation

NASA Technical Reports Server (NTRS)

Clark, T. L.; Slotboom, D. R.; Vaidya, P. G.

1981-01-01

The effect of inlet shape on forward radiated fan tone noise directivities was investigated under experimentally simplified zero flow conditions. Simulated fan tone noise was radiated to the far field through various shaped zero flow inlets. Baseline data were collected for the simplest baffled and unbaffled straight pipe inlets. These data compared well with prediction. The more general inlet shapes tested were the conical, circular, and exponential surfaces of revolution and an asymmetric inlet achieved by cutting a straight pipe inlet at an acute angle. Approximate theories were developed for these general shapes and some comparisons with data are presented. The conical and exponential shapes produced directivities that differed considerably from the baseline data while the circular shape produced directivities similar to the baseline data. The asymmetric inlet produced asymmetric directivities with significant reductions over the straight pipe data for some angles.

21 CFR 880.6100 - Ethylene oxide gas aerator cabinet.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ethylene oxide gas aerator cabinet. 880.6100... Miscellaneous Devices § 880.6100 Ethylene oxide gas aerator cabinet. (a) Identification. An ethyene oxide gas... required to remove residual ethylene oxide (ETO) from wrapped medical devices that have undergone ETO...

Research About the Corosive Effects of FeCl3 in the Aeration Wastewater Basin

NASA Astrophysics Data System (ADS)

Panaitescu, C.; Petrescu, M. G.

2018-01-01

Biological aeration of industrial wastewater is a very impressive process in the treatment of wastewater. The involvement of chemical reagents in this process, however, implies the intensification of the corrosion processes due to both pollutants in the wastewater and the chemical reactions that occur when the coagulation / flocculation reagents are added. This paper explores the action of ferric chloride (FeCl3) on metallic parts in the aeration basin. The most affected structures are metal. At the classical basins the aeration systems were made of P295GH materials. The corrosion produced is uneven. The analysis of the high degree of corrosion was done according to the national and international standards. Finally, the paper supports the replacement of the existing aeration system with an anticorrosive material.

Bioreactor tests preliminary to landfill in situ aeration: a case study.

PubMed

Raga, Roberto; Cossu, Raffaello

2013-04-01

Lab scale tests in bioreactor were carried out in the framework of the characterization studies of a landfill where in situ aeration (possibly followed by landfill mining) had been proposed as part of the novel waste management strategy in a region in northern Italy. The tests were run to monitor the effects produced by aerobic conditions at different temperatures on waste sampled at different depths in the landfill, with focus on the carbon and nitrogen conversion during aeration. Temperatures ranging from 35 to 45°C were chosen, in order to evaluate possible inhibition of biodegradation processes (namely nitrification) at 45°C in the landfill. The results obtained showed positive effects of the aeration on leachate quality and a significant reduction of waste biodegradability. Although a delay of biodegradation processes was observed in the reactor run at 45°C, biodegradation rates increased after 2 months of aeration, providing very low values of the relevant parameters (as in the other aerated reactors) by the end of the study. Mass balances were carried out for TOC and NNH4(+); the findings obtained were encouraging and provided evidence of the effectiveness of carbon and nitrogen conversion processes in the aerated landfill simulation reactors. Copyright © 2012 Elsevier Ltd. All rights reserved.

The effect of aeration on the removal of wastewater-derived pharmaceutical residues from groundwater - a laboratory study.

PubMed

Burke, Victoria; Duennbier, Uwe; Massmann, Gudrun

2013-01-01

Several studies on waste- or drinking water treatment processes as well as on groundwater have recently shown that some pharmaceutical residues (PRs) are redox-sensitive. Hence, their (bio)degradation depends on the redox conditions prevalent in the aquifer. Groundwater, providing raw water for drinking water production, is often anoxic and aeration is a widespread treatment method applied mainly to eliminate unwanted iron and manganese from the water. As a side-effect, aeration may trigger the elimination of PRs. Within the present study the influence of aeration on the fate of a number of wastewater derived analgesics and their residues as well as several antimicrobial compounds was investigated. For this purpose, anoxic groundwater was transferred into stainless steel tanks, some of which were aerated while others were continuously kept anoxic. Results prove that the degradation of six phenazone type compounds is dependent on oxygen availability and compounds are efficiently removed under oxic conditions only. Concerning the antimicrobials, doxycycline and trimethoprim were better removed during aeration, whereas a slightly improved removal under anoxic conditions was observed for clindamycin, roxithromycin and clarithromycin. The study provides first laboratory proof of the redox-sensitivity of several organic trace pollutants. In addition, results demonstrate that aeration is an effective treatment for the elimination of a number of wastewater derived PRs.

Microalgae population dynamics in photobioreactors with secondary sewage effluent as culture medium

PubMed Central

Marchello, Adriano E.; Lombardi, Ana T.; Dellamano-Oliveira, Maria José; de Souza, Clovis W.O.

2015-01-01

Nitrogen and phosphorus present in sewage can be used for microalgae growth, possibiliting cost reduction in the production of microalgae at the same time that it decreases the eutrophication potential of the effluent. This research aimed at monitoring the native community of microalgae and coliform bacteria in a secondary effluent from anaerobic municipal sewage treatment. Two treatments (aerated and non-aerated) were performed to grow microalgae under semi-controlled conditions in semi-closed photobioreactors in a greenhouse. The results showed no significant pH and coliforms (total and Escherichia coli ) variation between treatments. Nutrient concentrations were reduced supporting microalgae growth up to 10 7 cells.mL −1 independent of aeration. Exponential growth was obtained from the first day for the non-aerated, but a 5 day lag phase of growth was obtained for the aerated. Chlorella vulgaris was the dominant microalgae (99.9%) in both treatments. In the aerated, 5 algae classes were detected (Chlorophyceae, Cyanophyceae, Chrysophyceae, Bacillariophyceae and Euglenophyceae), with 12 taxa, whereas in the non-aerated, 2 classes were identified (Chlorophyceae and Cyanophyceae), with 5 taxa. We concluded that effluent is viable for microalgae growth, especially Chlorella vulgaris, at the same time that the eutrophication potential and coliforms are decreased, contributing for better quality of the final effluent. PMID:26221091

New jet-aeration system using 'Supercavitation'.

PubMed

Schmid, Andreas

2010-03-01

A newly developed fine bubble aeration system, by which air is transferred under supercavitation conditions, shows a clearly better performance than traditional, well-known aerators that rely on the jet-pump principle and its performance can be compared to oxygen transfer rates achieved in membrane and foil plate aerators. A prototype supercavitation aerator installed at a sewage treatment plant revealed an air input rate, which was about one third lower than that of the jet-pump system, which it replaced. In spite of this low air input rate, the daily demand of pure oxygen for the additionally installed membrane aeration system went down by approximately 49%, from the original level of about 1,200 m(3)/day to about 600 m(3)/day-and this over a test period of more than 7 months. The observed high oxygen transfer rates cannot be explained by traditional mass transfer mechanisms. It is assumed that a large amount of water being transferred into the gas phase by supercavitation contacting directly oxygen also in the gas phase and thereby overcoming mass transfer hindrances which might be favoured by hydroxyl radicals. With this new aerator, during the first 3 months of test phase, already more than 10,000 Euros had been saved because of the reduced pure oxygen demand.

Effect of intermittent aeration strategies on treatment performance and microbial community of an IFAS reactor treating municipal waste water.

PubMed

Singh, Nitin Kumar; Bhatia, Akansha; Kazmi, Absar Ahmad

2017-11-01

This study investigated the effect of various intermittent aeration (IA) cycles on organics and nutrient removal, and microbial communities in an integrated fixed-film activated sludge (IFAS) reactor treating municipal waste water. Average effluent biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids, total nitrogen (TN) and total phosphorus (TP) values were noted as 20, 50, 30, 12 and 1.5 mgL -1 , respectively, in continuous aeration mode. A total of four operational conditions (run 1, continuous aeration; run 2, 150/30 min aeration on/off time; run 3, 120/60 min aeration on/off time and run 4, 90/60 min aeration on/off time) were investigated in IFAS reactor assessment. Among the all examined IA cycles, IA phase 2 gave the maximum COD and BOD removals with values recorded as 97% and 93.8%, respectively. With respect to nutrient removal (TN and TP), IA phase 1 was found to be optimum. Pathogen removal efficiency of present system was recorded as 90-95% during the three phases. With regard to settling characteristics, pilot showed poor settling during IA schedules, which was also evidenced by high sludge volume index values. Overall, IA could be used as a feasible way to improve the overall performance of IFAS system.

Photosynthetic aeration in biological wastewater treatment using immobilized microalgae-bacteria symbiosis.

PubMed

Praveen, Prashant; Loh, Kai-Chee

2015-12-01

Chlorella vulgaris encapsulated in alginate beads were added into a bioreactor treating synthetic wastewater using Pseudomonas putida. A symbiotic CO2/O2 gas exchange was established between the two microorganisms for photosynthetic aeration of wastewater. During batch operation, glucose removal efficiency in the bioreactor improved from 50% in 12 h without aeration to 100% in 6 h, when the bioreactor was aerated photosynthetically. During continuous operation, the bioreactor was operated at a low hydraulic retention time of 3.3 h at feed concentrations of 250 and 500 mg/L glucose. The removal efficiency at 500 mg/L increased from 73% without aeration to 100% in the presence of immobilized microalgae. The initial microalgae concentration was critical to achieve adequate aeration, and the removal rate increased with increasing microalgae concentration. The highest removal rate of 142 mg/L-h glucose was achieved at an initial microalgae concentration of 190 mg/L. Quantification of microalgae growth in the alginate beads indicated an exponential growth during symbiosis, indicating that the bioreactor performance was limited by oxygen production rates. Under symbiotic conditions, the chlorophyll content of the immobilized microalgae increased by more than 30%. These results indicate that immobilized microalgae in symbiosis with heterotrophic bacteria are promising in wastewater aeration.

Type of homogenization and fat loss during continuous infusion of human milk.

PubMed

García-Lara, Nadia Raquel; Escuder-Vieco, Diana; Alonso Díaz, Clara; Vázquez Román, Sara; De la Cruz-Bértolo, Javier; Pallás-Alonso, Carmen Rosa

2014-11-01

Substantial fat loss may occur during continuous feeding of human milk (HM). A decrease of fat loss has been described following homogenization. Well-established methods of homogenization of HM for routine use in the neonatal intensive care unit (NICU) would be desirable. We compared the loss of fat based on the use of 3 different methods for homogenizing thawed HM during continuous feeding. Sixteen frozen donor HM samples were thawed, homogenized with ultrasound and separated into 3 aliquots ("baseline agitation," "hourly agitation," and "ultrasound"), and then frozen for 48 hours. Aliquots were thawed again and a baseline agitation was applied. Subsequently, aliquots baseline agitation and hourly agitation were drawn into a syringe, while ultrasound was applied to aliquot ultrasound before it was drawn into a syringe. The syringes were loaded into a pump (2 mL/h; 4 hours). At hourly intervals the hourly agitation infusion was stopped, the syringe was disconnected and gently shaken. During infusion, samples from the 3 groups were collected hourly for analysis of fat and caloric content. The 3 groups of homogenization showed similar fat content at the beginning of the infusion. For fat, mean (SD) hourly changes of -0.03 (0.01), -0.09 (0.01), and -0.09 (0.01) g/dL were observed for the hourly agitation, baseline agitation, and ultrasound groups, respectively. The decrease was smaller for the hourly agitation group (P < .001). When thawed HM is continuously infused, a smaller fat loss is observed when syringes are agitated hourly versus when ultrasound or a baseline homogenization is used. © The Author(s) 2014.

Efficacy of antipsychotics in dementia depended on the definition of patients and outcomes: a meta-epidemiological study.

PubMed

Smeets, C H W; Zuidema, S U; Hulshof, T A; Smalbrugge, M; Gerritsen, D L; Koopmans, R T C M; Luijendijk, H J

2018-05-18

Postulating that efficacy of antipsychotics for agitation and psychosis in dementia is best estimated in trials among patients with these symptoms and with symptom-specific outcomes, we investigated whether clinically broader definitions affected the pooled efficacy. Trials were searched in multiple databases and categorized according to patient population (agitated, psychotic, mixed) and outcome scale (agitation, psychosis, generic). Standardized mean differences with 95% confidence intervals were calculated for conventional and atypical antipsychotics separately. Thirty trials met our inclusion criteria. Conventional antipsychotics might have a small effect in agitated patients on agitation scales (-0.44; -0.88, 0.01), and in psychotic patients on psychosis scales (-0.31; -0.61, -0.02). There was no effect on generic scales. Efficacy of atypical antipsychotics was not established in agitated patients on agitation scales (-0.15; -0.43, 0.13), and in psychotic patients on psychosis scales (-0.11; -0.20, -0.03), but was small in mixed patients on agitation scales (-0.29; -0.40, -0.18). Pooled efficacy of antipsychotics for agitation and psychosis in dementia is biased when based on trials that included patients without these target symptoms, or on results measured with generic scales. This finding is important for reviewers and guideline developers who select trials for reviews. Copyright © 2018. Published by Elsevier Inc.

Anterior Ethmoidal Nerve Block in Prevention of Postoperative Agitation

ClinicalTrials.gov

2018-02-08

Postoperative Agitation: Impaired Awareness, Abnormal Cognitive Function, Confusion, and Verbal and Physical Agitation During Recovery From General Anesthesia; Deviated Nasal Septum; Chronic Rhinosinusitis (Diagnosis); Nasal Polyps

Effects of indoor gardening on sleep, agitation, and cognition in dementia patients--a pilot study.

PubMed

Lee, Y; Kim, S

2008-05-01

A pilot study was performed to examine the efficacy of indoor gardening on sleep, agitation and cognition of dementia patients. Twenty-three institutionalized dementia patients who had sleep disturbance and/or agitation participated in a 5-week study protocol of 1 week of baseline and 4 weeks of treatment. The study design was a one group repeated measures study. For the first and fifth week of the study period, sleep patterns, agitation, and cognition were evaluated using a sleep diary, Modified Cohen-Mansfield Agitation Inventory and revised Hasegawa Dementia Scale respectively. Significant improvement in wake after sleep onset, nap, nocturnal sleep time, and nocturnal sleep efficiency was identified. On the contrary sleep onset time, wake-up time, total sleep time did not change after indoor gardening. Agitation and cognition score was significantly improved. Indoor gardening was found to be effective for sleep, agitation, and cognition of dementia patients. Randomized controlled studies of larger sample size are needed to confirm treatment effect.

3-D Numerical Simulation for Gas-Liquid Two-Phase Flow in Aeration Tank

NASA Astrophysics Data System (ADS)

Xue, R.; Tian, R.; Yan, S. Y.; Li, S.

In the crafts of activated sludge treatment, oxygen supply and the suspending state of activated sludge are primary factors to keep biochemistry process carrying on normally. However, they are all controlled by aeration. So aeration is crucial. The paper focus on aeration, use CFD software to simulate the field of aeration tank which is designed by sludge load method. The main designed size of aeration tank is: total volume: 20 000 m3; corridor width: 8m; total length of corridors: 139m; number of corridors: 3; length of one single corridor: 48m; effective depth: 4.5m; additional depth: 0.5m. According to the similarity theory, a geometrical model is set up in proportion of 10:1. The way of liquid flow is submerge to avoid liquid flow out directly. The grid is plotted by dividing the whole computational area into two parts. The bottom part which contains gas pipe and gas exit hole and the above part which is the main area are plotted by tetrahedron and hexahedron respectively. In boundary conditions, gas is defined as the primary-phase, and liquid is defined as the secondary-phase. Choosing mixture model, two-phase flow field of aeration tank is simulated by solved the Continuity equation for the mixture, Momentum equation for the mixture, Volume fraction equation for the secondary phases and Relative velocity formula when gas velocity is 10m/s, 20m/s, 30m/s. what figure shows is the contour of velocity magnitude for the mixture phase when gas velocity is 20m/s. Through analysis, the simulation tendency is agreed with actual running of aeration tank. It is feasible to use mixture model to simulate flow field of aeration tank by fluent software. According to the simulation result, the better velocity of liquid or gas (the quantity of inlet air) can be chosen by lower cost, and also the performance of aeration tank can be forecast. It will be helpful for designing and operation.

Effects of intermittent and continuous aeration on accelerative stabilization and microbial population dynamics in landfill bioreactors.

PubMed

Sang, Nguyen Nhu; Soda, Satoshi; Inoue, Daisuke; Sei, Kazunari; Ike, Michihiko

2009-10-01

Performance and microbial population dynamics in landfill bioreactors were investigated in laboratory experiments. Three reactors were operated without aeration (control reactor, CR), with cyclic 6-h aeration and 6-h non-aeration (intermittently aerated reactor, IAR), and with continuous aeration (continuously aerated reactor, CAR). Each reactor was loaded with high-organic solid waste. The performance of IAR was highest among the reactors up to day 90. The respective solid weight, organic matter content, and waste volume on day 90 in the CR, IAR, and CAR were 50.9, 39.1, and 47.5%; 46.5, 29.3 and 35.0%; and 69, 38, and 53% of the initial values. Organic carbon and nitrogen compounds in leachate in the IAR and the CAR showed significant decreases in comparison to those in the CR. The most probable number (MPN) values of fungal 18S rDNA in the CAR and the IAR were higher than those in the CR. Terminal restriction fragment length polymorphism analysis showed that unique and diverse eubacterial and archaeal communities were formed in the IAR. The intermittent aeration strategy was favorable for initiation of solubilization of organic matter by the aerobic fungal populations and the reduction of the acid formation phase. Then the anaerobic H(2)-producing bacteria Clostridium became dominant in the IAR. Sulfate-reducing bacteria, which cannot use acetate/sulfate but which instead use various organics/sulfate as the electron donor/acceptor were also dominant in the IAR. Consequently, Methanosarcinales, which are acetate-utilizing methanogens, became the dominant archaea in the IAR, where high methane production was observed.

PIV Study of Aeration Efficient of Stepped Spillway System

NASA Astrophysics Data System (ADS)

Abas, M. A.; Jamil, R.; Rozainy, M. R.; Zainol, M. A.; Adlan, M. N.; Keong, C. W.

2017-06-01

This paper investigates the three-dimensional (3D) simulation of Cascade aerator system using Lattice Boltzmann simulation and laboratory experiment was carried out to investigate the flow, aeration and cavitation in the spillway. Different configurations of stepped spillway are designed in this project in order to investigate the relationship between the configurations of stepped spillway and cavitation in the flow. The aeration in the stepped spillway will also be investigated. The experimental result will be compared with the simulated result at the end of this project. The figure of flow pattern at the 3rd step in simulation and experiment for Set 1 and Set 2 are look similar between LBM simulation and the experiment findings. This will provide a better understanding of the cavitation, aeration and flow in different configurations of the stepped spillway. In addition the occurrence of negative pressure region in the stepped spillway, increases the possibility of cavitation to occur. The cavitation will damage the structure of the stepped spillway. Furthermore, it also founds that increasing in barrier thickness of the stepped spillway will improve the aeration efficiency and reduce the cavitation in stepped spillway.

Simultaneous removal of organic matter and salt ions from coal gasification wastewater RO concentrate and microorganisms succession in a MBR.

PubMed

Jia, Shengyong; Han, Yuxing; Zhuang, Haifeng; Han, Hongjun; Li, Kun

2017-10-01

A lab-scale membrane bioreactor (MBR) with intermittent aeration was operated to treat the reverse osmosis concentrate derived from coal gasification wastewater. Results showed intermittent aeration represented slight effect on organic matter reduction but significant effect on nitrite and nitrate reduction, with 6h aeration and 6h non-aeration, removal efficiencies of organic matter, chloride, sulfate, nitrite and nitrate reached 48.35%, 40.91%, 34.28%, -36.05% and 64.34%, respectively. High-throughput sequencing showed a microorganisms succession from inoculated activated sludge (S1) to activated sludge in MBR (S2) with high salinity. Richness and diversity of microorganisms in S2 was lower than S1 and the community structure of S1 exhibited more even than S2. The most relative abundance of genus in S1 and S2 were unclassified_Desulfarculaceae (9.39%) and Roseibaca (62.1%), respectively. High salinity and intermittent aeration represented different influence on the denitrifying genus, and non-aeration phase provided feasible dissolved oxygen condition for denitrifying genera realizing denitrification. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical Oxygen Demand abatement in sewage using Micro-Aeration Enhanced Ecological Floating Bed

NASA Astrophysics Data System (ADS)

Shi, Hongle; Zhou, Gaofeng; Liu, Yiqing; Tan, Jiancong; Fu, Yongsheng

2018-02-01

The traditional ecological floating bed combined with micro-aeration system and artificial medium was developed for the removal of contaminants and remediation of surface water. This micro-aeration enhanced ecological floating bed (MAEEFB) consisted of aeration unit, microbial processing unit and aquatic plant unit. Batch experiments were conducted in different operating conditions on the removal of chemical oxygen demand (COD) in the sewage using MAEEFB. The removal rate of COD by MAEEFB, enhanced ecological floating bed (EEFB) and traditional ecological floating bed (TEFB) in the same reaction conditions was 59.2%, 56.9% and 30.6%, respectively, indicating that the combination of micro-aeration system and artificial medium could enhance the removal efficiency of COD in TEFB. In MAEEFB, the aeration intensity should be designed reasonablely considering both treatment efficiency and operation cost. Only increasing the specific surface area of the packing cannot effectively improve the purification efficiency of water. Factors like packing material, ability of intercepting organics and complicated extent of microorganisms attaching on the packing should also be considered.

Pathway governing nitrogen removal in artificially aerated constructed wetlands: Impact of aeration mode and influent chemical oxygen demand to nitrogen ratios.

PubMed

Hou, Jie; Wang, Xin; Wang, Jie; Xia, Ling; Zhang, Yiqing; Li, Dapeng; Ma, Xufa

2018-06-01

This study aimed at assessing the influence of aeration mode and influent COD/N ratio on nitrogen removal in constructed wetlands (CWs). The results showed that a simultaneous partial nitrification, anammox and denitrification (SNAD) process was established in the intermittent aerated V1. While nitrogen removal pathway gradually changed from partial nitrification-denitrification to complete nitrification-denitrification along with reducing COD/N ratio in the continuous limited aerated V2. Effective inhibition of NOBs under intermittent aeration conditions, good retention of anammox bacteria biomass and much faster depletion of COD prior to substantial NH 4 + -N conversion jointly led to the successful achievement of stable SNDA process with elevated influent COD/N ratios in V1. Furthermore, the presence of SNAD ensured a robust ammonium (84-92%) and TN (80-91%) removal efficiency in V1 under varying COD loading rates. In contrast, the TN removal efficiency decreased rapidly along with the reducing influent COD/N ratios in V2. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterizing the experience of agitation in patients with bipolar disorder and schizophrenia.

PubMed

Roberts, Jenna; Gracia Canales, Alfredo; Blanthorn-Hazell, Sophee; Craciun Boldeanu, Anca; Judge, Davneet

2018-04-16

Agitation is a common manifestation of bipolar disorder and schizophrenia which includes symptoms ranging from inner tension and unease to violence and aggression. Much of the existing literature has focused on agitation in the acute setting, with the patient experience poorly defined. Thus, the aim of this study was to characterize agitation and its management from a patient perspective, with the focus on those who reside in the community. Surveys were completed across Germany, Spain and the UK by 583 community dwelling patients with schizophrenia or bipolar disorder who experienced episodes of agitation. Patients were recruited via either their physician or through patient support groups. The survey captured information on demographics, disease characteristics, frequency of agitation episodes and different pre-defined severity levels ranging from mild to severe, symptoms experienced during an episode, awareness of agitation and coping strategies employed by the patient. Statistics were descriptive in nature. The most commonly reported symptoms during an episode of agitation were feeling uneasy (n = 373, 64%), restless (n = 368, 63%) or nervous (n = 368, 63%). Patients experienced an average of 22.4 (SD 57.2) mild, 15.4 (SD 61.2) moderate, 6.8 (SD 63.3) moderate-intense and 2.9 (SD 24.4) severe episodes within the last 12 months; on average 2.7 (SD 6.8) required hospital attendance. Half of patients (n = 313) had attended hospital due to agitation. In total, 71% of patients (n = 412) were aware they were becoming agitated either always or sometimes and 61% of patients (n = 347) were aware of agitation triggers either always or sometimes. The majority of patients reported being able to sometimes control their agitation (56%, n = 329) but 16% (n = 94) stated that there is typically nothing they can do. To cope with episodes 55% (n = 125) of schizophrenia patients and 66% (n = 234) of bipolar disorder patients reported taking prescribed medication. Community based patients with schizophrenia and bipolar disorder reported frequently experiencing agitation episodes which they defined most commonly as feeling uneasy, restless or nervous. A range of coping strategies were reported but they were not always successful, highlighting an area of unmet need in this population.

Aeration strategy for biofilm cultivation of the microalga Scenedesmus dimorphus.

PubMed

Ji, Chunli; Wang, Junfeng; Liu, Tianzhong

2015-10-01

Biofilm cultivation of microalgae may be useful for biofuel production. However, many aspects for this cultivation method have not been well assessed. Accordingly, aeration strategy for biofilm cultivation of Scenedesmus dimorphus has been explored. Biomass, lipid and triacylglycerol (TAG) productivity in increased S. dimorphus as the CO2 concentration increased within 0.038-0.5% and kept constant with further increases. The biomass, lipid and TAG productivity increased with the speed increasing and an obvious threshold point was observed at 6.6 ml(-2) min(-1). The lipid and TAG content was unaffected by the aeration rate. Both the CO2 concentration as well as aeration speed affected the growth of S. dimorphus in biofilm cultivation. The optimized aeration strategy for biofilm cultivation was continuous air flow enriched with 1% CO2 (v/v) at 6.6 ml(-2) min(-1).

Does psychomotor agitation in major depressive episodes indicate bipolarity? Evidence from the Zurich Study.

PubMed

Angst, Jules; Gamma, Alex; Benazzi, Franco; Ajdacic, Vladeta; Rössler, Wulf

2009-02-01

Kraepelin's partial interpretation of agitated depression as a mixed state of "manic-depressive insanity" (including the current concept of bipolar disorder) has recently been the focus of much research. This paper tested whether, how, and to what extent both psychomotor symptoms, agitation and retardation in depression are related to bipolarity and anxiety. The prospective Zurich Study assessed psychiatric and somatic syndromes in a community sample of young adults (N = 591) (aged 20 at first interview) by six interviews over 20 years (1979-1999). Psychomotor symptoms of agitation and retardation were assessed by professional interviewers from age 22 to 40 (five interviews) on the basis of the observed and reported behaviour within the interview section on depression. Psychiatric diagnoses were strictly operationalised and, in the case of bipolar-II disorder, were broader than proposed by DSM-IV-TR and ICD-10. As indicators of bipolarity, the association with bipolar disorder, a family history of mania/hypomania/cyclothymia, together with hypomanic and cyclothymic temperament as assessed by the general behavior inventory (GBI) [15], and mood lability (an element of cyclothymic temperament) were used. Agitated and retarded depressive states were equally associated with the indicators of bipolarity and with anxiety. Longitudinally, agitation and retardation were significantly associated with each other (OR = 1.8, 95% CI = 1.0-3.2), and this combined group of major depressives showed stronger associations with bipolarity, with both hypomanic/cyclothymic and depressive temperamental traits, and with anxiety. Among agitated, non-retarded depressives, unipolar mood disorder was even twice as common as bipolar mood disorder. Combined agitated and retarded major depressive states are more often bipolar than unipolar, but, in general, agitated depression (with or without retardation) is not more frequently bipolar than retarded depression (with or without agitation), and pure agitated depression is even much less frequently bipolar than unipolar. The findings do not support the hypothesis that agitated depressive syndromes are mixed states. The results are limited to a population up to the age of 40; bipolar-I disorders could not be analysed (small N).

Ventilatory protective strategies during thoracic surgery: effects of alveolar recruitment maneuver and low-tidal volume ventilation on lung density distribution.

PubMed

Kozian, Alf; Schilling, Thomas; Schütze, Hartmut; Senturk, Mert; Hachenberg, Thomas; Hedenstierna, Göran

2011-05-01

The increased tidal volume (V(T)) applied to the ventilated lung during one-lung ventilation (OLV) enhances cyclic alveolar recruitment and mechanical stress. It is unknown whether alveolar recruitment maneuvers (ARMs) and reduced V(T) may influence tidal recruitment and lung density. Therefore, the effects of ARM and OLV with different V(T) on pulmonary gas/tissue distribution are examined. Eight anesthetized piglets were mechanically ventilated (V(T) = 10 ml/kg). A defined ARM was applied to the whole lung (40 cm H(2)O for 10 s). Spiral computed tomographic lung scans were acquired before and after ARM. Thereafter, the lungs were separated with an endobronchial blocker. The pigs were randomized to receive OLV in the dependent lung with a V(T) of either 5 or 10 ml/kg. Computed tomography was repeated during and after OLV. The voxels were categorized by density intervals (i.e., atelectasis, poorly aerated, normally aerated, or overaerated). Tidal recruitment was defined as the addition of gas to collapsed lung regions. The dependent lung contained atelectatic (56 ± 10 ml), poorly aerated (183 ± 10 ml), and normally aerated (187 ± 29 ml) regions before ARM. After ARM, lung volume and aeration increased (426 ± 35 vs. 526 ± 69 ml). Respiratory compliance enhanced, and tidal recruitment decreased (95% vs. 79% of the whole end-expiratory lung volume). OLV with 10 ml/kg further increased aeration (atelectasis, 15 ± 2 ml; poorly aerated, 94 ± 24 ml; normally aerated, 580 ± 98 ml) and tidal recruitment (81% of the dependent lung). OLV with 5 ml/kg did not affect tidal recruitment or lung density distribution. (Data are given as mean ± SD.) The ARM improves aeration and respiratory mechanics. In contrast to OLV with high V(T), OLV with reduced V(T) does not reinforce tidal recruitment, indicating decreased mechanical stress.

The use of an aeration system to prevent thermal stratification of a freshwater impoundment and its effect on downstream fish assemblages.

PubMed

Miles, N G; West, R J

2011-03-01

Warm-water riverine fish assemblages were investigated downstream of an impoundment before and after thermal stratification and the associated cold-water pollution was prevented using an aeration system. Temperatures below the dam significantly increased after installation of the aeration system and this correlated with an increased abundance and greater number of species downstream. Overall, aeration appeared to be beneficial for both the lake (upstream) and the downstream riverine environments. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Agitation After Subarachnoid Hemorrhage: A Frequent Omen of Hospital Complications Associated with Worse Outcomes.

PubMed

Reznik, Michael E; Schmidt, J Michael; Mahta, Ali; Agarwal, Sachin; Roh, David J; Park, Soojin; Frey, Hans Peter; Claassen, Jan

2017-06-01

Agitated delirium is frequent following acute brain injury, but data are limited in patients with subarachnoid hemorrhage (SAH). We examined incidence, risk factors, and consequences of agitation in these patients in a single-center retrospective study. We identified all patients treated with antipsychotics or dexmedetomidine from a prospective observational cohort of patients with spontaneous SAH. Agitation was confirmed by chart review. Outcomes were assessed at 12 months using the modified Rankin Scale (mRS), Telephone Interview for Cognitive Status (TICS), and Lawton IADL (Instrumental Activities of Daily Living) scores. Independent predictors were identified using logistic regression. From 309 SAH patients admitted between January 2011 and December 2015, 52 (17 %) developed agitation, frequently in the first 72 h (50 %) and in patients with Hunt-Hess grades 3-4 (12 % of grades 1-2, 28 % of grades 3-4, 8 % of grade 5). There was also a significant association between agitation and a history of cocaine use or prior psychiatric diagnosis. Agitated patients were more likely to develop multiple hospital complications; and in half of these patients, complications were diagnosed within 24 h of agitation onset. Agitation was associated with IADL impairment at 12 months (Lawton >8; p = 0.03, OR 2.7, 95 % CI, 1.1-6.8) in non-comatose patients (Hunt-Hess 1-4), but not with functional outcome (mRS >3), cognitive impairment (TICS ≤30), or ICU/hospital length of stay after controlling for other predictors. Agitation occurs frequently after SAH, especially in non-comatose patients with higher clinical grades. It is associated with the development of multiple hospital complications and may have an independent impact on long-term outcomes.

Agitation after subarachnoid hemorrhage: a frequent omen of hospital complications associated with worse outcomes

PubMed Central

Reznik, Michael E.; Schmidt, J. Michael; Mahta, Ali; Agarwal, Sachin; Roh, David J.; Park, Soojin; Frey, Hans Peter; Claassen, Jan

2017-01-01

Purpose Agitated delirium is frequent following acute brain injury, but data are limited in patients with subarachnoid hemorrhage (SAH). We examined incidence, risk factors, and consequences of agitation in these patients in a single-center retrospective study. Methods We identified all patients treated with antipsychotics or dexmedetomidine from a prospective observational cohort of patients with spontaneous SAH. Agitation was confirmed by chart review. Outcomes were assessed at 12 months using the modified Rankin Scale (mRS), Telephone Interview for Cognitive Status (TICS), and Lawton-IADL (Instrumental Activities of Daily Living) score. Independent predictors were identified using logistic regression. Results From 309 SAH patients admitted between 1/2011 and 12/2015, 52 (17%) developed agitation, frequently in the first 72 hours (50%) and in patients with Hunt-Hess grades 3–4 (12% of grades 1–2, 28% of grades 3–4, 8% of grade 5). There was also a significant association between agitation and a history of cocaine use or prior psychiatric diagnosis. Agitated patients were more likely to develop multiple hospital complications, and in half of these patients complications were diagnosed within 24 hours of agitation onset. Agitation was associated with IADL impairment at 12 months (Lawton >8; p = 0.03, OR 2.7, 95% CI 1.1–6.8) in non-comatose patients (Hunt-Hess 1–4), but not with functional outcome (mRS >3), cognitive impairment (TICS ≤30), or ICU/hospital length of stay after controlling for other predictors. Conclusion Agitation occurs frequently after SAH, especially in non-comatose patients with higher clinical grades. It is associated with the development of multiple hospital complications, and may have an independent impact on long-term outcomes. PMID:28008563

Optimal nonpharmacological management of agitation in Alzheimer's disease: challenges and solutions.

PubMed

Millán-Calenti, José Carlos; Lorenzo-López, Laura; Alonso-Búa, Begoña; de Labra, Carmen; González-Abraldes, Isabel; Maseda, Ana

2016-01-01

Many patients with Alzheimer's disease will develop agitation at later stages of the disease, which constitutes one of the most challenging and distressing aspects of dementia. Recently, nonpharmacological therapies have become increasingly popular and have been proven to be effective in managing the behavioral symptoms (including agitation) that are common in the middle or later stages of dementia. These therapies seem to be a good alternative to pharmacological treatment to avoid unpleasant side effects. We present a systematic review of randomized controlled trials (RCTs) focused on the nonpharmacological management of agitation in Alzheimer's disease (AD) patients aged 65 years and above. Of the 754 studies found, eight met the inclusion criteria. This review suggests that music therapy is optimal for the management of agitation in institutionalized patients with moderately severe and severe AD, particularly when the intervention includes individualized and interactive music. Bright light therapy has little and possibly no clinically significant effects with respect to observational ratings of agitation but decreases caregiver ratings of physical and verbal agitation. Therapeutic touch is effective for reducing physical nonaggressive behaviors but is not superior to simulated therapeutic touch or usual care for reducing physically aggressive and verbally agitated behaviors. Melissa oil aromatherapy and behavioral management techniques are not superior to placebo or pharmacological therapies for managing agitation in AD. Further research in clinical trials is required to confirm the effectiveness and long-term effects of nonpharmacological interventions for managing agitation in AD. These types of studies may lead to the development of future intervention protocols to improve the well-being and daily functioning of these patients, thereby avoiding residential care placement.

Safety and utility of acute electroconvulsive therapy for agitation and aggression in dementia.

PubMed

Acharya, Deepa; Harper, David G; Achtyes, Eric D; Seiner, Stephen J; Mahdasian, Jack A; Nykamp, Louis J; Adkison, Lesley; Van der Schuur White, Lori; McClintock, Shawn M; Ujkaj, Manjola; Davidoff, Donald A; Forester, Brent P

2015-03-01

Agitation and aggression are among the most frequent and disruptive behavioral complications of dementia that contribute to increased cost of care, hospitalization, caregiver burden, and risk of premature institutionalization. This current study examined the safety and efficacy of electroconvulsive therapy (ECT) as a treatment for behavioral disturbances in dementia. We hypothesized that ECT would result in reduced agitated and aggressive behaviors between baseline and discharge. Twenty-three participants admitted to McLean Hospital (Belmont, MA, USA) and Pine Rest Christian Mental Health Services (Grand Rapids, MI, USA), with a diagnosis of dementia who were referred for ECT to treat agitation and/or aggression, were enrolled in the study. We administered the Cohen-Mansfield Agitation Inventory-Short Form, Neuropsychiatric Inventory-Nursing Home Version, Cornell Scale for Depression in Dementia, and the Clinical Global Impression Scale at baseline, during, and after the ECT course. Regression analyses revealed a significant decrease from baseline to discharge on the Cohen-Mansfield Agitation Inventory (F(4,8) = 13.3; p = 0.006) and Neuropsychiatric Inventory (F(4,31) = 14.6; p < 0.001). There was no statistically significant change in scores on the Cornell Scale for Depression in Dementia. The Clinical Global Impression scores on average changed from a rating of "markedly agitated/aggressive" at baseline to "borderline agitated/aggressive" at discharge. Treatment with ECT was well tolerated by most participants; discontinuation of ECT occurred for two participants because of recurrence of agitation and for three participants because of adverse events. Electroconvulsive therapy may be a safe treatment option to reduce symptoms of agitation and aggression in patients with dementia whose behaviors are refractory to medication management. Copyright © 2014 John Wiley & Sons, Ltd.

Optimal nonpharmacological management of agitation in Alzheimer’s disease: challenges and solutions

PubMed Central

Millán-Calenti, José Carlos; Lorenzo-López, Laura; Alonso-Búa, Begoña; de Labra, Carmen; González-Abraldes, Isabel; Maseda, Ana

2016-01-01

Many patients with Alzheimer’s disease will develop agitation at later stages of the disease, which constitutes one of the most challenging and distressing aspects of dementia. Recently, nonpharmacological therapies have become increasingly popular and have been proven to be effective in managing the behavioral symptoms (including agitation) that are common in the middle or later stages of dementia. These therapies seem to be a good alternative to pharmacological treatment to avoid unpleasant side effects. We present a systematic review of randomized controlled trials (RCTs) focused on the nonpharmacological management of agitation in Alzheimer’s disease (AD) patients aged 65 years and above. Of the 754 studies found, eight met the inclusion criteria. This review suggests that music therapy is optimal for the management of agitation in institutionalized patients with moderately severe and severe AD, particularly when the intervention includes individualized and interactive music. Bright light therapy has little and possibly no clinically significant effects with respect to observational ratings of agitation but decreases caregiver ratings of physical and verbal agitation. Therapeutic touch is effective for reducing physical nonaggressive behaviors but is not superior to simulated therapeutic touch or usual care for reducing physically aggressive and verbally agitated behaviors. Melissa oil aromatherapy and behavioral management techniques are not superior to placebo or pharmacological therapies for managing agitation in AD. Further research in clinical trials is required to confirm the effectiveness and long-term effects of nonpharmacological interventions for managing agitation in AD. These types of studies may lead to the development of future intervention protocols to improve the well-being and daily functioning of these patients, thereby avoiding residential care placement. PMID:26955265

Health service use and costs associated with aggressiveness or agitation and containment in adult psychiatric care: a systematic review of the evidence.

PubMed

Rubio-Valera, Maria; Luciano, Juan V; Ortiz, José Miguel; Salvador-Carulla, Luis; Gracia, Alfredo; Serrano-Blanco, Antoni

2015-03-04

Agitation and containment are frequent in psychiatric care but little is known about their costs. The aim was to evaluate the use of services and costs related to agitation and containment of adult patients admitted to a psychiatric hospital or emergency service. Systematic searches of four electronic databases covering the period January 1998-January 2014 were conducted. Manual searches were also performed. Paper selection and data extraction were performed in duplicate. Cost data were converted to euros in 2014. Ten studies met inclusion criteria and were included in the analysis (retrospective cohorts, prospective cohorts and cost-of-illness studies). Evaluated in these studies were length of stay, readmission rates and medication. Eight studies assessed the impact of agitation on the length of stay and six showed that it was associated with longer stays. Four studies examined the impact of agitation on readmission and a statistically significant increase in the probability of readmission of agitated patients was observed. Two studies evaluated medication. One study showed that the mean medication dose was higher in agitated patients and the other found higher costs of treatment compared with non-agitated patients in the unadjusted analysis. One study estimated the costs of conflict and containment incurred in acute inpatient psychiatric care in the UK. The estimation for the year 2014 of total annual cost per ward for all conflict was €182,616 and €267,069 for containment based on updated costs from 2005. Agitation has an effect on healthcare use and costs in terms of longer length of stay, more readmissions and higher drug use. Evidence is scarce and further research is needed to estimate the burden of agitation and containment from the perspective of hospitals and the healthcare system.

Managing Agitation Associated with Schizophrenia and Bipolar Disorder in the Emergency Setting.

PubMed

Zeller, Scott L; Citrome, Leslie

2016-03-01

Patient agitation represents a significant challenge in the emergency department (ED), a setting in which medical staff are working under pressure dealing with a diverse range of medical emergencies. The potential for escalation into aggressive behavior, putting patients, staff, and others at risk, makes it imperative to address agitated behavior rapidly and efficiently. Time constraints and limited access to specialist psychiatric support have in the past led to the strategy of "restrain and sedate," which was believed to represent the optimal approach; however, it is increasingly recognized that more patient-centered approaches result in improved outcomes. The objective of this review is to raise awareness of best practices for the management of agitation in the ED and to consider the role of new pharmacologic interventions in this setting. The Best practices in Evaluation and Treatment of Agitation (BETA) guidelines address the complete management of agitation, including triage, diagnosis, interpersonal calming skills, and medicine choices. Since their publication in 2012, there have been further developments in pharmacologic approaches for dealing with agitation, including both new agents and new modes of delivery, which increase the options available for both patients and physicians. Newer modes of delivery that could be useful in rapidly managing agitation include inhaled, buccal/sublingual and intranasal formulations. To date, the only formulation administered via a non-intramuscular route with a specific indication for agitation associated with bipolar or schizophrenia is inhaled loxapine. Non-invasive formulations, although requiring cooperation from patients, have the potential to improve overall patient experience, thereby improving future cooperation between patients and healthcare providers. Management of agitation in the ED should encompass a patient-centered approach, incorporating non-pharmacologic approaches if feasible. Where pharmacologic intervention is necessary, a cooperative approach using non-invasive medications should be employed where possible.

An aeration control strategy for oxidation ditch processes based on online oxygen requirement estimation.

PubMed

Zhan, J X; Ikehata, M; Mayuzumi, M; Koizumi, E; Kawaguchi, Y; Hashimoto, T

2013-01-01

A feedforward-feedback aeration control strategy based on online oxygen requirements (OR) estimation is proposed for oxidation ditch (OD) processes, and it is further developed for intermittent aeration OD processes, which are the most popular type in Japan. For calculating OR, concentrations of influent biochemical oxygen demand (BOD) and total Kjeldahl nitrogen (TKN) are estimated online by the measurement of suspended solids (SS) and sometimes TKN is estimated by NH4-N. Mixed liquor suspended solids (MLSS) and temperature are used to estimate the required oxygen for endogenous respiration. A straightforward parameter named aeration coefficient, Ka, is introduced as the only parameter that can be tuned automatically by feedback control or manually by the operators. Simulation with an activated sludge model was performed in comparison to fixed-interval aeration and satisfying result of OR control strategy was obtained. The OR control strategy has been implemented at seven full-scale OD plants and improvements in nitrogen removal are obtained in all these plants. Among them, the results obtained in Yumoto wastewater treatment plant were presented, in which continuous aeration was applied previously. After implementing intermittent OR control, the total nitrogen concentration was reduced from more than 5 mg/L to under 2 mg/L, and the electricity consumption was reduced by 61.2% for aeration or 21.5% for the whole plant.

Optimum aerobic volume control based on continuous in-line oxygen uptake monitoring.

PubMed

Svardal, K; Lindtner, S; Winkler, S

2003-01-01

Dynamic adaptation of the aerated volume to changing load conditions is essential to maximise the nitrogen removal performance and to minimise energy consumption. A control strategy is presented which provides optimum aerobic volume control (OAV-control concept) based on continuous in-line oxygen uptake monitoring. For ammonium concentrations below 1 mg/l the oxygen uptake rate shows a strong and almost linear dependency on the ammonium concentration. Therefore, the oxygen uptake rate is an ideal indicator for the nitrification performance in activated sludge systems. The OAV-control concept provides dynamic variation of the minimum aerobic volume required for complete nitrification and therefore maximises the denitrification performance. In-line oxygen uptake monitoring is carried out by controlling the oxygen concentration in a continuous aerated zone of the aeration tank and measuring the total air flow to the aeration tank. The total air flow to the aeration tank is directly proportional to the current oxygen uptake rate and can therefore be used as an indicator for the required aerobic volume. The instrumentation requirements for installation of the OAV-control are relatively low, oxygen sensors in the aeration tank and an on-line air flow measurement are needed. This enables individual control of aeration tanks operated in parallel at low investment costs. The OAV-control concept is installed at the WWTP Linz-Asten (1 Mio PE) and shows very good results. Full scale results are presented.

Methanogenesis acceleration of fresh landfilled waste by micro-aeration.

PubMed

Shao, Li-Ming; He, Pin-Jing; Zhang, Hua; Yu, Xiao-Hua; Li, Guo-Jian

2005-01-01

When municipal solid waste (MSW) with high content of food waste is landfilled, the rapid hydrolysis of food waste results in the imbalance of anaerobic metabolism in the landfill layer, indicated by accumulation of volatile fatty acids (VFA) and decrease of pH value. This occurrence could lead to long lag time before the initiation of methanogenesis and to the production of strong leachate. Simulated landfill columns with forced aeration, with natural ventilation, and with no aeration, were monitored regarding their organics degradation rate with leachate recirculation. Hydrolysis reactions produced strong leachate in the column with no aeration. With forced aeration, the produced VFA could be effectively degraded, leading to the reduction in COD of the leachate effluent since the week 3. The CH4 in the landfill gas from the column with aeration rate of 0.39 m3/(m3 x d) and frequency of twice/d, leachate recirculation rate of 12.2 mm/d and frequency of twice/d, could amount to 40% (v/v) after only 20 weeks. This amount had increased up to 50% afterward even with no aeration. Most of COD in the recirculated leachate was removed. Using natural ventilation, CH4 could also be produced and the COD of the leachate effluent be reduced after 10 weeks of operation. However, the persistent existence of oxygen in the landfill layer yielded instability in methanogenesis process.

Generating CO(2)-credits through landfill in situ aeration.

PubMed

Ritzkowski, M; Stegmann, R

2010-04-01

Landfills are some of the major anthropogenic sources of methane emissions worldwide. The installation and operation of gas extraction systems for many landfills in Europe and the US, often including technical installations for energy recovery, significantly reduced these emissions during the last decades. Residual landfill gas, however, is still continuously produced after the energy recovery became economically unattractive, thus resulting in ongoing methane emissions for many years. By landfill in situ aeration these methane emissions can be widely avoided both, during the aeration process as well as in the subsequent aftercare period. Based on model calculations and online monitoring data the amount of avoided CO(2-eq). can be determined. For an in situ aerated landfill in northern Germany, acting as a case study, 83-95% (depending on the kind and quality of top cover) of the greenhouse gas emission potential could be reduced under strictly controlled conditions. Recently the United Nations Framework Convention on Climate Change (UNFCCC) has approved a new methodology on the "Avoidance of landfill gas emissions by in situ aeration of landfills" (UNFCCC, 2009). Based on this methodology landfill aeration projects might be considered for generation of Certified Emission Reductions (CERs) in the course of CDM projects. This paper contributes towards an evaluation of the potential of landfill aeration for methane emissions reduction. Copyright 2009 Elsevier Ltd. All rights reserved.

Ecophysiology of wetland plant roots: A modelling comparison of aeration in relation to species distribution

USGS Publications Warehouse

Sorrell, B.K.; Mendelssohn, I.A.; McKee, K.L.; Woods, R.A.

2000-01-01

This study examined the potential for inter-specific differences in root aeration to determine wetland plant distribution in nature. We compared aeration in species that differ in the type of sediment and depth of water they colonize. Differences in root anatomy, structure and physiology were applied to aeration models that predicted the maximum possible aerobic lengths and development of anoxic zones in primary adventitious roots. Differences in anatomy and metabolism that provided higher axial fluxes of oxygen allowed deeper root growth in species that favour more reducing sediments and deeper water. Modelling identified factors that affected growth in anoxic soils through their effects on aeration. These included lateral root formation, which occurred at the expense of extension of the primary root because of the additional respiratory demand they imposed, reducing oxygen fluxes to the tip and stele, and the development of stelar anoxia. However, changes in sediment oxygen demand had little detectable effect on aeration in the primary roots due to their low wall permeability and high surface impedance, but appeared to reduce internal oxygen availability by accelerating loss from laterals. The development of pressurized convective gas flow in shoots and rhizomes was also found to be important in assisting root aeration, as it maintained higher basal oxygen concentrations at the rhizome-root junctions in species growing into deep water. (C) 2000 Annals of Botany Company.

Influence of agitation speed on tannase production and morphology of Aspergillus niger FETL FT3 in submerged fermentation.

PubMed

Darah, I; Sumathi, G; Jain, K; Lim, S H

2011-12-01

Agitation speed was found to influence the tannase production and fungal growth of Aspergillus niger FETL FT3. The optimal agitation speed was at 200 rpm which produced 1.41 U/ml tannase and 3.75 g/l of fungal growth. Lower or higher agitation speeds than 200 rpm produced lower enzyme production and fungal growth. Based on the SEM and TEM micrograph observation, there was a significant correlation between agitation speed and the morphology of the fungal mycelia. The results revealed an increase of the enzyme production with the change of the fungal growth morphology from filamentous to pelleted growth forms. However, the exposure to higher shear stress with an increasing agitation speed of the shaker also resulted in lower biomass yields as well as enzyme production.

Enhancing antibacterial effect of sodium hypochlorite by low electric current-assisted sonic agitation

PubMed Central

Maden, Murat; Ertuğrul, İhsan Furkan; Erik, Cevat Emre; Yetiş, Ceylan Çağıl; Tuncer, Yasin; Kahriman, Mesud

2017-01-01

Background This research focused on the effects of low electric current (μE)-assisted sonic agitation of sodium hypochlorite on Enterococcus faecalis infected human root dentin. Methods Extracted human canine roots were instrumented, sterilized, and experimentally contaminated with E. faecalis. After incubation for 21 days, the presence of the biofilm was confirmed by scanning electron microscopy (n = 3). Roots were randomly divided into seven groups according to decontamination procedures: G1: no treatment; G2: sterile saline; G3: 5.25% sodium hypochlorite; G4: passive ultrasonic irrigation; G5: EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) agitation (EA); G6: μE agitation; and G7: μE-assisted sonic agitation. Fixed μE amperage and intensities were applied in G6 and G7. Following microbial sampling, bacterial colonies were counted using the direct plating method. Results Biofilm was not eradicated in any sample. The μE-assisted sonic agitation of sodium hypochlorite revealed the lowest cfu values (p<0.05), whereas there were no significant differences among the passive ultrasonic irrigation, EndoActivator and μE agitation alone (p>0.05). Conclusions Based on available evidence, the following conclusions were drawn: The μE-assisted sonic agitation increased the antibiofilm efficiency of sodium hypochlorite than passive ultrasonic irrigation and EndoActivator. The μE-assisted sonic agitation on 5.25% sodium hypochlorite is not capable to eradicate biofilms at 10mA energy level in 60s. PMID:28854274

Enhancing antibacterial effect of sodium hypochlorite by low electric current-assisted sonic agitation.

PubMed

Maden, Murat; Ertuğrul, İhsan Furkan; Orhan, Ekim Onur; Erik, Cevat Emre; Yetiş, Ceylan Çağıl; Tuncer, Yasin; Kahriman, Mesud

2017-01-01

This research focused on the effects of low electric current (μE)-assisted sonic agitation of sodium hypochlorite on Enterococcus faecalis infected human root dentin. Extracted human canine roots were instrumented, sterilized, and experimentally contaminated with E. faecalis. After incubation for 21 days, the presence of the biofilm was confirmed by scanning electron microscopy (n = 3). Roots were randomly divided into seven groups according to decontamination procedures: G1: no treatment; G2: sterile saline; G3: 5.25% sodium hypochlorite; G4: passive ultrasonic irrigation; G5: EndoActivator (Dentsply Tulsa Dental Specialties, Tulsa, OK) agitation (EA); G6: μE agitation; and G7: μE-assisted sonic agitation. Fixed μE amperage and intensities were applied in G6 and G7. Following microbial sampling, bacterial colonies were counted using the direct plating method. Biofilm was not eradicated in any sample. The μE-assisted sonic agitation of sodium hypochlorite revealed the lowest cfu values (p<0.05), whereas there were no significant differences among the passive ultrasonic irrigation, EndoActivator and μE agitation alone (p>0.05). Based on available evidence, the following conclusions were drawn: The μE-assisted sonic agitation increased the antibiofilm efficiency of sodium hypochlorite than passive ultrasonic irrigation and EndoActivator. The μE-assisted sonic agitation on 5.25% sodium hypochlorite is not capable to eradicate biofilms at 10mA energy level in 60s.

7 CFR 201.55a - Moisture and aeration of substratum.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 3 2013-01-01 2013-01-01 false Moisture and aeration of substratum. 201.55a Section... ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.55a Moisture and aeration of substratum. (a) The substratum must be moist enough to supply the needed moisture to...

7 CFR 201.55a - Moisture and aeration of substratum.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 3 2014-01-01 2014-01-01 false Moisture and aeration of substratum. 201.55a Section... ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.55a Moisture and aeration of substratum. (a) The substratum must be moist enough to supply the needed moisture to...

7 CFR 201.55a - Moisture and aeration of substratum.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 3 2012-01-01 2012-01-01 false Moisture and aeration of substratum. 201.55a Section... ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.55a Moisture and aeration of substratum. (a) The substratum must be moist enough to supply the needed moisture to...

Identifying and treating agitated behaviors in the long-term care setting.

PubMed

Hastings, S N; Thompson-Heisterman, A; Farrell, S P

1999-01-01

This article provides information on identification, assessment, and intervention techniques for agitated behaviors in the long-term care setting. Although the emphasis is on prevention and management of agitation, the article offers suggestions to assist health care providers in differentiating between delirium, psychosis, depression, anxiety, and dementia, which may place a resident at risk for agitation. Basic treatment approaches for each of these disorders is also reviewed.

Individual music therapy for agitation in dementia: an exploratory randomized controlled trial.

PubMed

Ridder, Hanne Mette O; Stige, Brynjulf; Qvale, Liv Gunnhild; Gold, Christian

2013-01-01

Agitation in nursing home residents with dementia leads to increase in psychotropic medication, decrease in quality of life, and to patient distress and caregiver burden. Music therapy has previously been found effective in treatment of agitation in dementia care but studies have been methodologically insufficient. The aim of this study was to examine the effect of individual music therapy on agitation in persons with moderate/severe dementia living in nursing homes, and to explore its effect on psychotropic medication and quality of life. In a crossover trial, 42 participants with dementia were randomized to a sequence of six weeks of individual music therapy and six weeks of standard care. Outcome measures included agitation, quality of life and medication. Agitation disruptiveness increased during standard care and decreased during music therapy. The difference at -6.77 (95% CI (confidence interval): -12.71, -0.83) was significant (p = 0.027), with a medium effect size (0.50). The prescription of psychotropic medication increased significantly more often during standard care than during music therapy (p = 0.02). This study shows that six weeks of music therapy reduces agitation disruptiveness and prevents medication increases in people with dementia. The positive trends in relation to agitation frequency and quality of life call for further research with a larger sample.

Nitrogen pools and flows during lab-scale degradation of old landfilled waste under different oxygen and water regimes.

PubMed

Brandstätter, Christian; Laner, David; Fellner, Johann

2015-09-01

Nitrogen emissions from municipal solid waste (MSW) landfills occur primarily via leachate, where they pose a long-term pollution problem in the form of ammonium. In-situ aeration was proposed as a remediation measure to mitigate nitrogenous landfill emissions, turning the anaerobic environment to anoxic and subsequently aerobic. As in-depth studies of the nitrogen cycle during landfill aeration had been largely missing, it was the aim of this work to establish a detailed nitrogen balance for aerobic and anaerobic degradation of landfilled MSW based on lab-scale experiments, and also investigating the effect of different water regimes on nitrogen transformation during aeration. Six landfill simulation reactors were operated in duplicate under different conditions: aerated wet (with water addition and recirculation), aerated dry (without water addition) and anaerobic (wet). The results showed that more than 78 % of the initial total nitrogen (TNinit) remained in the solids in all set ups, with the highest nitrogen losses achieved with water addition during aeration. In this case, gaseous nitrogen losses (as N2 due to denitrification) amounted up to 16.6 % of TNinit and around 4 % of TNinit was discharged via leachate. The aerated dry set-up showed lower denitrification rates (2.6-8.8 % of TNinit was released as N2), but was associated with the highest N2O emissions (3.8-3.9 % of TNinit). For the anaerobic treatment the main pathway of nitrogen discharge was the leachate, where NH4 accounted for around 8 % of TNinit. These findings provide the basis for improved management strategies to enhance nitrogen removal during in-situ aeration of old landfills.

Coupling of bio-PRB and enclosed in-well aeration system for remediation of nitrobenzene and aniline in groundwater.

PubMed

Liu, Na; Ding, Feng; Wang, Liu; Liu, Peng; Yu, Xiaolong; Ye, Kang

2016-05-01

A laboratory-scale bio-permeable reactive barrier (bio-PRB) was constructed and combined with enclosed in-well aeration system to treat nitrobenzene (NB) and aniline (AN) in groundwater. Batch-style experiments were first conducted to evaluate the effectiveness of NB and AN degradation, using suspension (free cells) of degrading consortium and immobilized consortium by a mixture of perlite and peat. The NB and AN were completely degraded in <3 days using immobilized consortium, while 3-5 days were required using free cells. The O2 supply efficiency of an enclosed in-well aeration system was assessed in a box filled with perlite and peat. Dissolved O2 (DO) concentrations increased to 8-12 mg L(-1) in 12 h for sampling ports within 12 cm of the aeration well. A diffusion coefficient as 33.5 cm(2) s(-1) was obtained. The DO concentration was >4 mg L(-1) when the aeration system was applied into the bio-PRB system. The NB and AN were effectively removed when the aeration system was functional in the bio-PRB. The removal efficiency decreased when the aeration system malfunctioned for 20 days, thus indicating that DO was an important factor for the degradation of NB and AN. The regain of NB and AN removal after the malfunction indicates the robustness of degradation consortium. No original organics and new formed by-products were observed in the effluent. The results indicate that NB and AN in groundwater can be completely mineralized in a bio-PRB equipped with enclosed in-well aeration system and filled with perlite and peat attached with degrading consortium.

Nitrogen removal in wood chip combined substrate baffled subsurface-flow constructed wetlands: impact of matrix arrangement and intermittent aeration.

PubMed

Li, Huai; Chi, Zifang; Yan, Baixing; Cheng, Long; Li, Jianzheng

2017-02-01

In this study, two lab-scale baffled subsurface-flow constructed wetlands (BSFCWs), including gravel-wood chips-slag and gravel-slag-wood chips, were operated at different intermittent aeration to evaluate the effect of artificial aeration and slow-released carbon source on the treatment efficiency of high-strength nitrogen wastewater. Results indicated that gravel-slag-wood chips extended aerobic/anaerobic alternating environment to gravel and slag zones and maintained anaerobic condition in the subsequent wood chip section. The order of gravel-slag-wood chip was more beneficial to pollutant removal. Sufficient carbon source supply resulted from wood-chip-framework substrate simultaneously obtained high removals of COD (97%), NH 4 + -N (95%), and TN (94%) in BSFCWs at 2 h aeration per day. The results suggest that intermittent aeration combined with wood chips could achieve high nitrogen removal in BSFCWs.

Effect of a large-sized silicone sheet upon recovery of mastoid aeration after mastoidectomy.

PubMed

Kazama, Kyosuke; Takahashi, Haruo; Kaieda, Satoru; Iwanaga, Tetsu; Yamamoto-Fukuda, Tomomi; Yoshida, Haruo; Kumagami, Hidetaka; Takasaki, Kenji

2008-06-01

To evaluate the effect of our large-sized silicone sheet upon postoperative recovery of mastoid aeration in ears after surgery including mastoidectomy and soft-wall reconstruction (SWR). Retrospective chart review in a tertiary care center. Recovery of mastoid aeration was assessed by CT 4 to 12 months after surgery on 72 ears (69 patients), in which the silicone sheet covering from the eustachian tube (ET) to the mastoid was placed after SWR procedure with mastoidectomy were done for their chronic otitis media. Results were compared with those with a small silicone sheet. Recovery of mastoid aeration was significantly better in the large-silicone-sheet group than in the small-silicone-sheet group (chi(2) value = 11.7146, P = 0.0006). This preliminary study suggested that our large-sized silicone sheet may be effective for postoperative recovery of mastoid aeration even in ears operated with SWR procedure.

Improving microalgal growth with small bubbles in a raceway pond with swing gas aerators.

PubMed

Yang, Zongbo; Cheng, Jun; Liu, Jianzhong; Zhou, Junhu; Cen, Kefa

2016-09-01

A novel swing gas aerator was developed to generate small bubbles for improving the mass transfer coefficient and microalgal growth rate in a raceway pond. A high-speed photography system (HSP) was used to measure the bubble diameter and generation time, and online precise dissolved oxygen probes and pH probes were used to measure the mass transfer coefficient and mixing time. Bubble generation time and diameter decreased by 21% and 9%, respectively, when rubber gas aerators were swung in the microalgae solution. When water pump power and gas aeration rate increased in a raceway pond with swing gas aerators and oscillating baffles (SGAOB), bubble generation time and diameter decreased but solution velocity and mass transfer coefficient increased. The mass transfer coefficient increased by 25% and the solution velocity increased by 11% when SGAOB was used, and the microalgal biomass yield increased by 18%. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Application of music therapy for managing agitated behavior in older people with dementia].

PubMed

Sung, Huei-Chuan; Chang, Anne M; Abbey, Jennifer

2006-10-01

Older people with dementia may display negative emotions, memory problems, sleep disturbance, and agitated behavior. Among these symptoms, agitated behavior has been identified by families and nursing staff as the care problem that presents the greatest challenge. Several studies have found that music therapy reduced agitated behaviors in those with dementia and recommended use of music as an effective strategy in managing this behavioral problem. Music therapy represents a lower cost, effective care approach that nursing staff can easily learn and apply to those with dementia. Furthermore, reductions in agitated behavior in dementia patients that result from music therapy can also alleviate caregiver stress and burden of care, leading to improvements in the health and quality of life of both dementia patients and their caregivers. This paper aims to introduce the principles and application of music therapy in the management of agitated behavior in those with dementia.

Effect of Aromatherapy Massage on Agitation and Depressive Mood in Individuals With Dementia.

PubMed

Yang, Ya-Ping; Wang, Chi-Jane; Wang, Jing-Jy

2016-09-01

The current study examined the effects of aromatherapy massage on alleviating agitation and depressive mood in individuals with dementia. A randomized controlled trial and repeated measures design was conducted. A total of 59 participants were randomly assigned to intervention or control groups. The intervention group received aromatherapy massage once per week for 8 weeks. Results indicated no significant changes over time in overall agitation for either group, but agitation decreased from Week 1 to Week 5 for the intervention group. In addition, the overall depressive symptoms decreased significantly over time for the intervention group compared to the control group (p < 0.001). However, changes in agitation within 24 hours following aromatherapy massage showed some significant changes in Weeks 5 and 9. Aromatherapy massage can be an effective and safe intervention to alleviate specific agitated behaviors and depressive mood in individuals with dementia. [Journal of Gerontological Nursing, 42(9), 38-46.]. Copyright 2016, SLACK Incorporated.

A novel methodology to quantify nitrous oxide emissions from full-scale wastewater treatment systems with surface aerators.

PubMed

Ye, Liu; Ni, Bing-Jie; Law, Yingyu; Byers, Craig; Yuan, Zhiguo

2014-01-01

The quantification of nitrous oxide (N2O) emissions from open-surface wastewater treatment systems with surface aerators is difficult as emissions from the surface aerator zone cannot be easily captured by floating hoods. In this study, we propose and demonstrate a novel methodology to estimate N2O emissions from such systems through determination of the N2O transfer coefficient (kLa) induced by surface aerators based on oxygen balance for the entire system. The methodology is demonstrated through its application to a full-scale open oxidation ditch wastewater treatment plant with surface aerators. The estimated kLa profile based on a month-long measurement campaign for oxygen balance, intensive monitoring of dissolved N2O profiles along the oxidation ditch over a period of four days, together with mathematical modelling, enabled to determine the N2O emission factor from this treatment plant (0.52 ± 0.16%). Majority of the N2O emission was found to occur in the surface aerator zone, which would be missed if the gas hood method was applied alone. Copyright © 2013 Elsevier Ltd. All rights reserved.

Legionella and non-Legionella bacteria in a biological treatment plant.

PubMed

Fykse, Else Marie; Aarskaug, Tone; Thrane, Ingjerd; Blatny, Janet Martha

2013-02-01

Legionella pneumophila were previously identified in the aeration ponds (up to 10(10) CFU/L) of a biological wastewater treatment plant at Borregaard Ind. Ltd., Sarpsborg, Norway, and in air samples (up to 3300 CFU/m(3)) collected above the aeration ponds. After 3 outbreaks of Legionnaires' disease reported in this area in 2005 and 2008, the aeration ponds of the plant were shut down by the Norwegian authorities in September 2008. The aim of the present work was to analyze the Legionella and non-Legionella bacterial communities in the aeration ponds before and during the shutdown process and to identify potential human pathogens. The non-Legionella bacterial community was investigated in selected samples during the shutdown process by 16S rDNA sequencing of clone libraries (400 clones) and growth analysis. The concentration of L. pneumophila and Pseudomonas spp. DNA were monitored by quantitative PCR. Results showed a decrease in the concentration of L. pneumophila and Pseudomonas spp. during the shutdown. This was accompanied by a significant change in the composition of the bacterial community in the aeration ponds. This study demonstrated that several advanced analytical methods are necessary to characterize the bacterial population in complex environments, such as the industrial aeration ponds.

Comparison between lab- and full-scale applications of in situ aeration of an old landfill and assessment of long-term emission development after completion.

PubMed

Hrad, Marlies; Gamperling, Oliver; Huber-Humer, Marion

2013-10-01

Sustainable landfilling has become a fundamental objective in many modern waste management concepts. In this context, the in situ aeration of landfills has been recognised for its potential to convert conventional anaerobic landfills into biological stabilised state, whereby both current and potential (long-term) emissions of the landfilled waste are mitigated. In recent years, different in situ aeration concepts have been successfully applied in Europe, North America and Asia, all pursuing different objectives and strategies. In Austria, the first full-scale application of in situ landfill aeration by means of low pressure air injection and simultaneous off-gas collection and treatment was implemented on an old, small municipal solid waste (MSW) landfill (2.6ha) in autumn 2007. Complementary laboratory investigations were conducted with waste samples taken from the landfill site in order to provide more information on the transferability of the results from lab- to full-scale aeration measures. In addition, long-term emission development of the stabilised waste after aeration completion was assessed in an ongoing laboratory experiment. Although the initial waste material was described as mostly stable in terms of the biological parameters gas generation potential over 21days (GP21) and respiration activity over 4days (RA4), the lab-scale experiments indicated that aeration, which led to a significant improvement of leachate quality, was accompanied by further measurable changes in the solid waste material under optimised conditions. Even 75weeks after aeration completion the leachate, as well as gaseous emissions from the stabilised waste material, remained low and stayed below the authorised Austrian discharge limits. However, the application of in situ aeration at the investigated landfill is a factor 10 behind the lab-based predictions after 3years of operation, mainly due to technical limitations in the full-scale operation (e.g. high air flow resistivity due to high water content of waste and temporarily high water levels within the landfill; limited efficiency of the aeration wells). In addition, material preparation (e.g. sieving, sorting and homogenisation) prior to the emplacement in Landfill Simulation Reactors (LSRs) must be considered when transferring results from lab- to full-scale application. Copyright © 2013 Elsevier Ltd. All rights reserved.

Psychiatric Evaluation of the Agitated Patient: Consensus Statement of the American Association for Emergency Psychiatry Project BETA Psychiatric Evaluation Workgroup

PubMed Central

Stowell, Keith R; Florence, Peter; Harman, Herbert J; Glick, Rachel L

2012-01-01

It is difficult to fully assess an agitated patient, and the complete psychiatric evaluation usually cannot be completed until the patient is calm enough to participate in a psychiatric interview. Nonetheless, emergency clinicians must perform an initial mental status screening to begin this process as soon as the agitated patient presents to an emergency setting. For this reason, the psychiatric evaluation of the agitated patient can be thought of as a 2-step process. First, a brief evaluation must be aimed at determining the most likely cause of agitation, so as to guide preliminary interventions to calm the patient. Once the patient is calmed, more extensive psychiatric assessment can be completed. The goal of the emergency assessment of the psychiatric patient is not necessarily to obtain a definitive diagnosis. Rather, ascertaining a differential diagnosis, determining safety, and developing an appropriate treatment and disposition plan are the goals of the assessment. This article will summarize what components of the psychiatric assessment can and should be done at the time the agitated patient presents to the emergency setting. The complete psychiatric evaluation of the patient whose agitation has been treated successfully is beyond the scope of this article and Project BETA (Best practices in Evaluation and Treatment of Agitation), but will be outlined briefly to give the reader an understanding of what a full psychiatric assessment would entail. Other issues related to the assessment of the agitated patient in the emergency setting will also be discussed. PMID:22461916

Design of top covers supporting aerobic in situ stabilization of old landfills - An experimental simulation in lysimeters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hrad, Marlies; Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at; Wimmer, Bernhard

2012-12-15

Highlights: Black-Right-Pointing-Pointer Tested engineered covers as surrogate to gas extraction during and after in situ aeration. Black-Right-Pointing-Pointer Examined how covers influence gas emissions, water balance and leachate generation. Black-Right-Pointing-Pointer Investigated effect of top covers on air-distribution in waste mass during aeration. Black-Right-Pointing-Pointer We suggest criteria and cover design to meet the demands during and after aeration. Black-Right-Pointing-Pointer Such cover systems may offer greenhouse gas emission reduction also after active aeration. - Abstract: Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top coversmore » that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 Multiplication-Sign 2 Multiplication-Sign 3 m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH{sub 4} loadings up to 300 l CH{sub 4}/m{sup 2} d. In addition, the compost material provided high air permeability even at 100% water holding capacity (WHC). In contrast, the more cohesive, mineral soil cover was expected to cause a notably uniform distribution of the injected air within the waste layer. Laboratory results also revealed sufficient air permeability of the soil materials (TS-F and SS-Z) placed in lysimeter C. However, at higher compaction density SS-Z became impermeable at 100% WHC. Methane emissions from the reference lysimeter with the smaller substrate cover (12-52 g CH{sub 4}/m{sup 2} d) were significantly higher than fluxes from the other lysimeters (0-19 g CH{sub 4}/m{sup 2} d) during in situ aeration. Regarding water balance, lysimeters covered with compost and compost-sand mixture, showed the lowest leachate rate (18-26% of the precipitation) due to the high water holding capacity and more favourable plant growth conditions compared to the lysimeters with mineral, more cohesive, soil covers (27-45% of the precipitation). On the basis of these results, the authors suggest a layered top cover system using both compost material as well as mineral soil in order to support active low-pressure aeration. Conventional soil materials with lower permeability may be used on top of the landfill body for a more uniform aeration of the waste due to an increased resistance to vertical gas flow. A compost cover may be built on top of the soil cover underlain by a gas distribution layer to improve methane oxidation rates and minimise water infiltration. By planting vegetation with a high transpiration rate, the leachate amount emanating from the landfill could be further minimised. The suggested design may be particularly suitable in combination with intermittent in situ aeration, in the later stage of an aeration measure, or at very small sites and shallow deposits. The top cover system could further regulate water infiltration into the landfill and mitigate residual CH{sub 4} emissions, even beyond the time of active aeration.« less

Treating agitation with dexmedetomidine in the ICU.

PubMed

Boyer, Jeanne

2009-01-01

Patients in the intensive care unit frequently experience delirium, anxiety, and agitation, with a variety of treatments used. This article discusses the role of an alpha-adrenoceptor agonist, dexmedetomidine, and its clinical relevance and advantages for the agitated patient.

Positive effect of reduced aeration rate on growth and stereospecificity of DL-malic acid consumption by Azospirillum brasilense: improving the shelf life of a liquid inoculant formulation.

PubMed

Carrasco-Espinosa, Karen; García-Cabrera, Ramsés I; Bedoya-López, Andrea; Trujillo-Roldán, Mauricio A; Valdez-Cruz, Norma A

2015-02-10

Azospirillum brasilense has significance as a growth promoter in plants of commercial interest. Two industrial native strains (Start and Calf), used as a part of an inoculant formulation in Mexico during the last 15 years, were incubated in laboratory-scale pneumatic bioreactors at different aeration rates. In both strains, the positive effect of decreased aeration was observed. At the lowest (0.1 vvm, air volume/liquid volume×minute), the highest biomass were obtained for Calf (7.8 × 10(10)CFU/ml), and Start (2.9 × 10(9)CFU/ml). These were higher in one magnitude order compared to cultures carried out at 0.5 vvm, and two compared to those at 1.0 vvm. At lower aeration, both stereoisomeric forms of malic acid were consumed, but at higher aeration, just L-malate was consumed. A reduction in aeration allows an increase of the shelf life and the microorganism saved higher concentrations of polyhydroxybutyrate. The selected fermentation conditions are closely related to those prevalent in large-scale bioreactors and offer the possibility of achieving high biomass titles with high shelf life at a reduced costs, due to the complete use of a carbon source at low aeration of a low cost raw material as DL-malic acid mixture in comparison with the L-malic acid stereoisomer. Copyright © 2015 Elsevier B.V. All rights reserved.

A field study on phytoremediation of dredged sediment contaminated by heavy metals and nutrients: the impacts of sediment aeration.

PubMed

Wu, Juan; Yang, Lihua; Zhong, Fei; Cheng, Shuiping

2014-12-01

Compared to traditional chemical or physical treatments, phytoremediation has proved to be a cost-effective and environmentally sound alternative for remediation of contaminated dredged sediment. A field study was conducted in a sediment disposal site predominantly colonized by Typha angustifolia under different sediment moisture conditions to estimate the phytoremediation effects of dredged sediment. The moisture content was 37.30 % and 48.27 % in aerated and waterlogged sediment, respectively. Total nitrogen (TN) content was higher in the waterlogged sediment than in the aerated sediment. The total Cd contents were lower in aerated sediment, which was mainly resulted from the lower exchangeable fraction of Cd. The bioaccumulation of P, Cu and Pb in T. angustifolia was promoted by waterlogging, and the belowground tissue concentrations and accumulation factors (AFs) of Cu were higher than that of other metals, which can be explained by that Cu is an essential micronutrient for plants. Consistent with many previous studies, T. angustifolia showed higher metal levels in roots than in above-ground tissues at both the sediment conditions. Due to the improved biomass produced in the aerated sediment, the removals of nutrients and the metals by plant harvest were higher from aerated sediment than from waterlogged sediment. It was indicated that maintaining the dredged sediment aerated can avoid release risk and plant uptake of metals, while the opposite management option can promote phytoextraction of these contaminants.

Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum)

PubMed Central

Li, Yuan; Jia, Zongxia; Niu, Wenquan; Wang, Jingwei; Zhang, Mingzhi

2015-01-01

Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27–33, 34–57, 58–85, 86–99, and 27–99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34–57 DAS) and enlargement (58–85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment. PMID:26630675

Comparative study on the reactivity of Fe/Cu bimetallic particles and zero valent iron (ZVI) under different conditions of N2, air or without aeration.

PubMed

Xiong, Zhaokun; Lai, Bo; Yang, Ping; Zhou, Yuexi; Wang, Juling; Fang, Shuping

2015-10-30

In order to further compare the degradation capacity of Fe(0) and Fe/Cu bimetallic system under different aeration conditions, the mineralization of PNP under different aeration conditions has been investigated thoroughly. The results show that the removal of PNP by Fe(0) or Fe/Cu system followed the pseudo-first-order reaction kinetics. Under the optimal conditions, the COD removal efficiencies obtained through Fe(0) or Fe/Cu system under different aeration conditions followed the trend that Fe/Cu (air)>Fe/Cu (N2: 0-30 min, air: 30-120 min)>control-Fe (air)>Fe/Cu (without aeration)>Fe/Cu (N2)>control-Fe (N2). It revealed that dissolved oxygen (DO) could improve the mineralization of PNP, and Cu could enhance the reactivity of Fe(0). In addition, the degradation of PNP was further analyzed by using UV-vis, FTIR and GC/MS, and the results suggest that Fe/Cu bimetallic system with air aeration could completely break the benzene ring and NO2 structure of PNP and could generate the nontoxic and biodegradable intermediate products. Meanwhile, most of these intermediate products were further mineralized into CO2 and H2O, which brought about a high COD removal efficiency (83.8%). Therefore, Fe/Cu bimetallic system with air aeration would be a promising process for toxic refractory industry wastewater. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum).

PubMed

Li, Yuan; Jia, Zongxia; Niu, Wenquan; Wang, Jingwei; Zhang, Mingzhi

2015-01-01

Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27-33, 34-57, 58-85, 86-99, and 27-99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34-57 DAS) and enlargement (58-85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment.

Efficient removal of perfluorooctane sulfonate from aqueous film-forming foam solution by aeration-foam collection.

PubMed

Meng, Pingping; Deng, Shubo; Maimaiti, Ayiguli; Wang, Bin; Huang, Jun; Wang, Yujue; Cousins, Ian T; Yu, Gang

2018-07-01

Aqueous film-forming foams (AFFFs) used in fire-fighting are one of the main contamination sources of perfluorooctane sulfonate (PFOS) to the subterranean environment, requiring high costs for remediation. In this study, a method that combined aeration and foam collection was presented to remove PFOS from a commercially available AFFF solution. The method utilized the strong surfactant properties of PFOS that cause it to be highly enriched at air-water interfaces. With an aeration flow rate of 75 mL/min, PFOS removal percent reached 96% after 2 h, and the PFOS concentration in the collected foam was up to 6.5 mmol/L, beneficial for PFOS recovery and reuse. Increasing the aeration flow rate, ionic strength and concentration of co-existing surfactant, as well as decreasing the initial PFOS concentration, increased the removal percents of PFOS by increasing the foam volume, but reduced the enrichment of PFOS in the foams. With the assistance of a co-existing hydrocarbon surfactant, PFOS removal percent was above 99.9% after aeration-foam collection for 2 h and the enrichment factor exceeded 8400. Aeration-foam collection was less effective for short-chain perfluoroalkyl substances due to their relatively lower surface activity. Aeration-foam collection was found to be effective for the removal of high concentrations of PFOS from AFFF-contaminated wastewater, and the concentrated PFOS in the collected foam can be reused. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dexmedetomidine use in the ED for control of methamphetamine-induced agitation.

PubMed

Lam, Rex Pui Kin; Yip, Wai Lam; Wan, Chi Keung; Tsui, Matthew Sik Hon

2017-04-01

Chemical restraint is often required to control agitation induced by methamphetamine. Dexmedetomidine is an α-2 adrenergic receptor agonist with sedative, analgesic, and sympatholytic properties. Its use in the emergency department (ED) to control methamphetamine-induced agitation has not been reported. To report two cases of methamphetamine-induced agitation successfully sedated with dexmedetomidine in the ED. The first case was a 42-year-old man with unstable emotion and violent behaviours after smoking methamphetamine. His agitation did not respond to a large cumulative dose of benzodiazepines (10mg of diazepam and 332mg of midazolam) administered over 48h and sedation was achieved with dexmedetomidine. The second case was a 38-year-old methamphetamine user with unstable emotion and recurrent episodes of agitation despite repeated doses of benzodiazepines, whose agitation was controlled with dexmedetomidine infusion. In both cases, dexmedetomidine apparently reduced the dose of benzodiazepines needed to achieve adequate sedation. Transient falls in blood pressure and slowing of the heart rate were noted, which resolved either spontaneously or after reducing the infusion rate without requiring drug treatment. Dexmedetomidine can be considered as an adjunct for chemical restraint when standard treatment fails to control the agitation induced by methamphetamine, but patient's hemodynamic state should be monitored closely during administration. Its efficacy and safety in the ED warrant further evaluation with prospective controlled trials. Copyright © 2016 Elsevier Inc. All rights reserved.

Individual music therapy for agitation in dementia: an exploratory randomized controlled trial

PubMed Central

Stige, Brynjulf; Qvale, Liv Gunnhild; Gold, Christian

2013-01-01

Objectives: Agitation in nursing home residents with dementia leads to increase in psychotropic medication, decrease in quality of life, and to patient distress and caregiver burden. Music therapy has previously been found effective in treatment of agitation in dementia care but studies have been methodologically insufficient. The aim of this study was to examine the effect of individual music therapy on agitation in persons with moderate/severe dementia living in nursing homes, and to explore its effect on psychotropic medication and quality of life. Method: In a crossover trial, 42 participants with dementia were randomized to a sequence of six weeks of individual music therapy and six weeks of standard care. Outcome measures included agitation, quality of life and medication. Results: Agitation disruptiveness increased during standard care and decreased during music therapy. The difference at −6.77 (95% CI (confidence interval): −12.71, −0.83) was significant (p = 0.027), with a medium effect size (0.50). The prescription of psychotropic medication increased significantly more often during standard care than during music therapy (p = 0.02). Conclusion: This study shows that six weeks of music therapy reduces agitation disruptiveness and prevents medication increases in people with dementia. The positive trends in relation to agitation frequency and quality of life call for further research with a larger sample. PMID:23621805

Utilizing whey protein isolate and polysaccharide complexes to stabilize aerated dairy gels.

PubMed

O'Chiu, Emily; Vardhanabhuti, Bongkosh

2017-05-01

Heated soluble complexes of whey protein isolate (WPI) with polysaccharides may be used to modify the properties of aerated dairy gels, which could be formulated into novel-textured high-protein desserts. The objective of this study was to determine the effect of polysaccharide charge density and concentration within a WPI-polysaccharide complex on the physical properties of aerated gels. Three polysaccharides having different degrees of charge density were chosen: low-methoxyl pectin, high-methoxyl type D pectin, and guar gum. Heated complexes were prepared by heating the mixed dispersions (8% protein, 0 to 1% polysaccharide) at pH 7. To form aerated gels, 2% glucono-δ-lactone was added to the dispersions of skim milk powder and heated complex and foam was generated by whipping with a handheld frother. The foam set into a gel as the glucono-δ-lactone acidified to a final pH of 4.5. The aerated gels were evaluated for overrun, drainage, gel strength, and viscoelastic properties. Without heated complexes, stable aerated gels could not be formed. Overrun of aerated gel decreased (up to 73%) as polysaccharide concentration increased from 0.105 to 0.315% due to increased viscosity, which limited air incorporation. A negative relationship was found between percent drainage and dispersion viscosity. However, plotting of drainage against dispersion viscosity separated by polysaccharide type revealed that drainage decreased most in samples with high-charge-density, low-methoxyl pectin followed by those with low-charge-density, high-methoxyl type D pectin. Aerated gels with guar gum (no charge) did not show improvement to stability. Rheological results showed no significant difference in gelation time among samples; therefore, stronger interactions between WPI and high-charge-density polysaccharide were likely responsible for increased stability. Stable dairy aerated gels can be created from WPI-polysaccharide complexes. High-charge-density polysaccharides, at concentrations that provide adequate viscosity, are needed to achieve stability while also maintaining dispersion overrun capabilities. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Use of soybean oil and ammonium sulfate additions to optimize secondary metabolite production.

PubMed

Junker, B; Mann, Z; Gailliot, P; Byrne, K; Wilson, J

1998-12-05

A valine-overproducing mutant (MA7040, Streptomyces hygroscopicus) was found to produce 1.5 to 2.0 g/L of the immunoregulant, L-683,590, at the 0.6 m3 fermentation scale in a simple batch process using soybean oil and ammonium sulfate-based GYG5 medium. Levels of both lower (L-683,795) and higher (HH1 and HH2) undesirable homolog levels were controlled adequately. This batch process was utilized to produce broth economically at the 19 m3 fermentation scale. Material of acceptable purity was obtained without the multiple pure crystallizations previously required for an earlier culture, MA6678, requiring valine supplementation for impurity control. Investigations at the 0.6 m3 fermentation scale were conducted, varying agitation, pH, initial soybean oil/ammonium sulfate charges, and initial aeration rate to further improve growth and productivity. Mid-cycle ammonia levels and lipase activity appeared to have an important role. Using mid-cycle soybean oil additions, a titer of 2.3 g/L of L-683,590 was obtained, while titers reached 2.7 g/L using mid-cycle soybean oil and ammonium sulfate additions. Both higher and lower homolog levels remained acceptable during this fed-batch process. Optimal timing of mid-cycle oil and ammonium sulfate additions was considered a critical factor to further titer improvements. Copyright 1998 John Wiley & Sons, Inc.

Microbial Beneficiation of Salem Iron Ore Using Penicillium purpurogenum

NASA Astrophysics Data System (ADS)

Mishra, M.; Pradhan, M.; Sukla, L. B.; Mishra, B. K.

2011-02-01

High alumina and silica content in the iron ore affects coke rate, reducibility, and productivity in a blast furnace. Iron ore is being beneficiated all around the world to meet the quality requirement of iron and steel industries. Choosing a beneficiation treatment depends on the nature of the gangue present and its association with the ore structure. The advanced physicochemical methods used for the beneficiation of iron ore are generally unfriendly to the environment. Biobeneficiation is considered to be ecofriendly, promising, and revolutionary solutions to these problems. A characterization study of Salem iron ore indicates that the major iron-bearing minerals are hematite, magnetite, and goethite. Samples on average contains (pct) Fe2O3-84.40, Fe (total)-59.02, Al2O3-7.18, and SiO2-7.53. Penicillium purpurogenum (MTCC 7356) was used for the experiment . It removed 35.22 pct alumina and 39.41 pct silica in 30 days in a shake flask at 10 pct pulp density, 308 K (35 °C), and 150 rpm. In a bioreactor experiment at 2 kg scale using the same organism, it removed 23.33 pct alumina and 30.54 pct silica in 30 days at 300 rpm agitation and 2 to 3 l/min aeration. Alumina and silica dissolution follow the shrinking core model for both shake flask and bioreactor experiments.

Characterization of metals released from coal fly ash during dredging at the Kingston ash recovery project.

PubMed

Bednar, A J; Averett, D E; Seiter, J M; Lafferty, B; Jones, W T; Hayes, C A; Chappell, M A; Clarke, J U; Steevens, J A

2013-09-01

A storage-pond dike failure occurred on December 22, 2008 at the Tennessee Valley Authority Kingston Fossil Plant resulting in the release of over 4million cubic meters (5million cubic yards) of fly ash. Approximately half of the released ash was deposited in the main channel of the Emory River, Tennessee, USA. Remediation efforts of the Emory River focused on hydraulic dredging, as well as mechanical excavation in targeted areas. However, agitation of the submerged fly ash during hydraulic dredging introduces river water into the fly ash material, which could promote dissolution and desorption of metals from the solid fly ash material. Furthermore, aeration of the dredge slurry could alter the redox state of metals in the fly ash material and thereby change their sorption, mobility, and toxicity properties. The research presented here focuses on the concentrations and speciation of metals during the fly ash recovery from the Emory River. Our results indicate that arsenite [As(III)] released from the fly ash material during dredging was slowly oxidized to arsenate [As(V)] in the slurry recovery system with subsequent removal through precipitation or sorption reactions with suspended fly ash material. Concentrations of other dissolved metals, including iron and manganese, also generally decreased in the ash recovery system prior to water discharge back to the river. Published by Elsevier Ltd.

Enhancement of oxygen mass transfer and gas holdup using palm oil in stirred tank bioreactors with xanthan solutions as simulated viscous fermentation broths.

PubMed

Mohd Sauid, Suhaila; Krishnan, Jagannathan; Huey Ling, Tan; Veluri, Murthy V P S

2013-01-01

Volumetric mass transfer coefficient (kLa) is an important parameter in bioreactors handling viscous fermentations such as xanthan gum production, as it affects the reactor performance and productivity. Published literatures showed that adding an organic phase such as hydrocarbons or vegetable oil could increase the kLa. The present study opted for palm oil as the organic phase as it is plentiful in Malaysia. Experiments were carried out to study the effect of viscosity, gas holdup, and kLa on the xanthan solution with different palm oil fractions by varying the agitation rate and aeration rate in a 5 L bench-top bioreactor fitted with twin Rushton turbines. Results showed that 10% (v/v) of palm oil raised the kLa of xanthan solution by 1.5 to 3 folds with the highest kLa value of 84.44 h(-1). It was also found that palm oil increased the gas holdup and viscosity of the xanthan solution. The kLa values obtained as a function of power input, superficial gas velocity, and palm oil fraction were validated by two different empirical equations. Similarly, the gas holdup obtained as a function of power input and superficial gas velocity was validated by another empirical equation. All correlations were found to fit well with higher determination coefficients.

Realm of Thermoalkaline Lipases in Bioprocess Commodities

PubMed Central

2018-01-01

For decades, microbial lipases are notably used as biocatalysts and efficiently catalyze various processes in many important industries. Biocatalysts are less corrosive to industrial equipment and due to their substrate specificity and regioselectivity they produced less harmful waste which promotes environmental sustainability. At present, thermostable and alkaline tolerant lipases have gained enormous interest as biocatalyst due to their stability and robustness under high temperature and alkaline environment operation. Several characteristics of the thermostable and alkaline tolerant lipases are discussed. Their molecular weight and resistance towards a range of temperature, pH, metal, and surfactants are compared. Their industrial applications in biodiesel, biodetergents, biodegreasing, and other types of bioconversions are also described. This review also discusses the advance of fermentation process for thermostable and alkaline tolerant lipases production focusing on the process development in microorganism selection and strain improvement, culture medium optimization via several optimization techniques (i.e., one-factor-at-a-time, surface response methodology, and artificial neural network), and other fermentation parameters (i.e., inoculums size, temperature, pH, agitation rate, dissolved oxygen tension (DOT), and aeration rate). Two common fermentation techniques for thermostable and alkaline tolerant lipases production which are solid-state and submerged fermentation methods are compared and discussed. Recent optimization approaches using evolutionary algorithms (i.e., Genetic Algorithm, Differential Evolution, and Particle Swarm Optimization) are also highlighted in this article. PMID:29666707

Effects of animal-assisted therapy on agitated behaviors and social interactions of older adults with dementia.

PubMed

Richeson, Nancy E

2003-01-01

The effects of a therapeutic recreation intervention using animal-assisted therapy (AAT) on the agitated behaviors and social interactions of older adults with dementia were examined using the Cohen-Mansfield Agitation Inventory and the Animal-Assisted Therapy Flow Sheet. In a pilot study, 15 nursing home residents with dementia participated in a daily AAT intervention for three weeks. Results showed statistically significant decreases in agitated behaviors and a statistically significant increase in social interaction pretest to post-test.

Aeration and drainage pathways of Prussak's space.

PubMed

Palva, T; Northrop, C; Ramsay, H

2001-01-01

the purpose of this study was to document the aeration and drainage pathways of Prussak's space. 55 temporal bones with an age range from neonate to 11 years of age were serially sectioned to 20 microns, every 10th section was saved and stained by Hematoxylin eosin. Each consecutive section was studied as to the connections of Prussak's space to adjacent compartments and measurements of the dimensions were made for both Prussak's space and its aeration pathways. the classic aeration pathway via the posterior pouch, as described by Prussak in 1867, was found in 34 ears (62%). In 19 (36%), aeration occurred superior to the posterior pouch in the region of the lower lateral attic and the upper mesotympanum. In these ears the posterior pouch had formed, but its superior limit ended blindly in the tympanic membrane. In two temporal bones the aeration pathway was from the anterior pouch and in these cases also a blind posterior pouch had developed. In one temporal bone an auxiliary pathway in addition to the route via the posterior pouch was through the roof (the lateral malleal ligamental fold) of Prussak's space to the overlying lateral malleal space. The height of the posterior pouch varied with a range from 0.5 to 2.4 mm, and the greatest width, which was towards the posterior tympanic spine, varied from 1.6 to 3.2 mm. The superiorly blind posterior pouch was shorter, ranging from 0.4 to 1.2 mm in height. The most frequent route of the chorda tympani nerve was running from 0.5 to 1 mm medial to the posterior malleal ligament in the anterior half of the pouch, joining it posteriorly, or it was connected to it by a short fold, 37 ears (67%). In 18 cases (33%) the chorda was surrounded by its own fold, thus entirely separate from the posterior malleal ligamental fold during its entire course across the tympanum. we have made a detailed documentation of the aeration and drainage pathways of Prussak's space and the findings concur, with important modifications, with Prussak's original description. There is no evidence for contemporary claims that Prussak's space would be aerated superiorly between the lateral incudal and malleal folds. Prussak's space and its aeration pathway is an unit of its own, entirely separate of the major epitympanic compartments which are aerated via the tympanic isthmus. Due to frequent disease processes in the lower lateral attic and posterior mesotympanum, Prussak's space and its aeration pathway are likely to become blocked. This may lead to obliteration of Prussak's space and to the development of retraction pocket or papillary ingrowth cholesteatoma.

Citalopram for the Treatment of Agitation in Alzheimer Dementia: Genetic Influences.

PubMed

Peters, Matthew E; Vaidya, Vijay; Drye, Lea T; Devanand, Davangere P; Mintzer, Jacobo E; Pollock, Bruce G; Porsteinsson, Anton P; Rosenberg, Paul B; Schneider, Lon S; Shade, David M; Weintraub, Daniel; Yesavage, Jerome; Lyketsos, Constantine G; Avramopoulos, Dimitri

2016-03-01

To assess potential genetic influences on citalopram treatment efficacy for agitation in individuals with Alzheimer dementia (AD). Six functional genetic variants were studied in the following genes: serotonin receptor 2A (HTR2A-T102C), serotonin receptor 2C (HTR2C-Cys23Ser), serotonin transporter (5HTT-LPR), brain-derived neurotropic factor (BDNF-Val66Met), apolipoprotein E (ε2, ε3, ε4 variants), and cytochrome P450 (CYP2C19). Treatment response by genotype was measured by (1) the agitation domain of the Neurobehavioral Rating Scale, (2) the modified Alzheimer Disease Cooperative Study-Clinical Global Impression of Change scale (mADCS-CGIC), (3) the agitation domain of the Neuropsychiatric Inventory (NPI), and (4) the Cohen-Mansfield Agitation Inventory. We utilized data from the Citalopram for Agitation in Alzheimer's Disease (CitAD) database. CitAD was a 9-week randomized, double-blind, placebo-controlled multicenter clinical trial showing significant improvement in agitation and caregiver distress in patients treated with citalopram. Proportional odds logistic regression and mixed effects models were used to examine the above-mentioned outcome measures. Significant interactions were noted on the NPI agitation domain for HTR2A (likelihood ratio [LR] = 6.19, df = 2, P = .04) and the mADCS-CGIC for HTR2C (LR = 4.33, df = 2, P = .02) over 9 weeks. Treatment outcomes in CitAD showed modest, although statistically significant, influence of genetic variation at HTR2A and HTR2C loci. Future studies should continue to examine the interaction of known genetic variants with antidepressant treatment in patients with AD having agitation. © The Author(s) 2015.

1064-nm Nd:YAG and 980-nm Diode Laser EDTA Agitation on the Retention of an Epoxy-Based Sealer to Root Dentin.

PubMed

Macedo, Helena Suleiman de; Messias, Danielle Cristine Furtado; Rached-Júnior, Fuad Jacob; Oliveira, Ligia Teixeira de; Silva-Sousa, Yara Teresinha Correa; Raucci-Neto, Walter

2016-01-01

Root canal irrigants are used to minimize the negative effects of smear layer on endodontic sealer retention. The aim of this study was to evaluate the efficacy of agitation of 17% ethylenediaminetetraacetic acid (EDTA) with ultrasonic, 1064-nm Nd:YAG and 980-nm diode laser on the retention of an epoxy-based sealer to the root canal walls. Forty single-rooted bovine teeth were instrumented with ProTaper rotary system and divided into four groups according to the final irrigation protocol (n = 10): (1) 17% EDTA (control); (2) 17% EDTA with 50-s ultrasonic agitation; (3) 17% EDTA with 50-s diode laser (2-W) agitation; and (4) 17% EDTA with 50-s Nd:YAG (1.5-W) laser agitation. After endodontic filling with gutta-percha F5 master cone and Sealer 26, the roots were sectioned at the cervical, middle, and apical root thirds to obtain 1.5-mm slices. Push-out tests were performed using a universal testing machine at a 1 mm/min crosshead speed. Data were analyzed using two-way ANOVA and Tukey's tests (α=0.05). Apical root thirds had significant higher retention values than cervical and middle thirds (p < 0.05). EDTA with 1064-nm Nd:YAG or 980-nm diode laser presented the highest retention values and was significantly different from EDTA with ultrasonic agitation and EDTA only (p < 0.05). Adhesive failures were predominant to EDTA only group. Mixed failures were predominant to all agitation groups. 1064-nm Nd:YAG and 980-nm diode laser EDTA agitation enhanced the retention of the epoxy-based sealer to the root canal walls compared with that due to EDTA only or EDTA with ultrasonic agitation.

Duration of Agitation, Fluctuations of Consciousness, and Associations with Outcome in Patients with Subarachnoid Hemorrhage.

PubMed

Reznik, Michael E; Mahta, Ali; Schmidt, J Michael; Frey, Hans-Peter; Park, Soojin; Roh, David J; Agarwal, Sachin; Claassen, Jan

2018-01-08

Agitation is common after subarachnoid hemorrhage (SAH) and may be independently associated with outcomes. We sought to determine whether the duration of agitation and fluctuating consciousness were also associated with outcomes in patients with SAH. We identified all patients with positive Richmond Agitation Sedation Scale (RASS) scores from a prospective observational cohort of patients with SAH from 2011 to 2015. Total duration of agitation was extrapolated for each patient using available RASS scores, and 24-h mean and standard deviation (SD) of RASS scores were calculated for each patient. We also calculated each patient's duration of substantial fluctuation of consciousness, defined as the number of days with 24-h RASS SD > 1. Patients were stratified by 3-month outcome using the modified Rankin scale, and associations with outcome were assessed via logistic regression. There were 98 patients with at least one positive RASS score, with median total duration of agitation 8 h (interquartile range [IQR] 4-18), and median duration of substantially fluctuating consciousness 2 days (IQR 1-3). Unfavorable 3-month outcome was significantly associated with a longer duration of fluctuating consciousness (odds ratio [OR] per day, 1.51; 95% confidence interval [CI], 1.04-2.20; p = 0.031), but a briefer duration of agitation (OR per hour, 0.94; 95% CI, 0.89-0.99; p = 0.031). Though a longer duration of fluctuating consciousness was associated with worse outcomes in our cohort, total duration of agitation was not, and may have had the opposite effect. Our findings should therefore challenge the intensity with which agitation is often treated in SAH patients.

SAFETY AND UTILITY OF ACUTE ELECTROCONVULSIVE THERAPY FOR AGITATION AND AGGRESSION IN DEMENTIA

PubMed Central

Acharya, Deepa; Harper, David G.; Achtyes, Eric D.; Seiner, Stephen J.; Mahdasian, Jack A.; Nykamp, Louis J.; Adkison, Lesley; Van der Schuur White, Lori; McClintock, Shawn M.; Ujkaj, Manjola; Davidoff, Donald A.; Forester, Brent P.

2015-01-01

Objective Agitation and aggression are among the most frequent and disruptive behavioral complications of dementia that contribute to increased cost of care, hospitalization, caregiver burden, and risk of premature institutionalization. This current study examined the safety and efficacy of electroconvulsive therapy (ECT) as a treatment for behavioral disturbances in dementia. We hypothesized that ECT would result in reduced agitated and aggressive behaviors between baseline and discharge. Methods Twenty-three participants admitted to McLean Hospital (Belmont, MA) and Pine Rest Christian Mental Health Services (Grand Rapids, MI), with a diagnosis of dementia who were referred for ECT to treat agitation and/or aggression, were enrolled in the study. We administered the Cohen-Mansfield Agitation Inventory (CMAI)-short form, Neuropsychiatric Inventory (NPI)-Nursing Home Version, Cornell Scale for Depression in Dementia (CSDD), and the Clinical Global Impression Scale (CGI) at baseline, during, and after the ECT course. Results Regression analyses revealed a significant decrease from baseline to discharge on the CMAI (F(4, 8) =13.3; p=0.006) and NPI (F(4, 31)= 14.6; p<0.001). There was no statistically significant change in scores on the CSDD. The CGI scores on average changed from a rating of “markedly agitated/aggressive” at baseline to “borderline agitated/aggressive” at discharge. Treatment with ECT was well tolerated by most participants; discontinuation of ECT occurred for two participants due to recurrence of agitation and for three participants due to adverse events. Conclusions ECT may be a safe treatment option to reduce symptoms of agitation and aggression in patients with dementia whose behaviors are refractory to medication management. PMID:24838521

Hydrodynamic effects on cell growth in agitated microcarrier bioreactors

NASA Technical Reports Server (NTRS)

Cherry, Robert S.; Papoutsakis, E. Terry

1988-01-01

The net growth rate of bovine embryonic kidney cells in microcarrier bioreactor is the result of a variable death rate imposed on a cell culture trying to grow at a constant intrinsic growth rate. The death rate is a function of the agitation conditions in the system, and increases at higher agitation because of increasingly energetic interactions of the cell covered microcarriers with turbulent eddies in the fluid. At very low agitation rates bead-bead bridging becomes important; the large clumps formed by bridging can interact with larger eddies than single beads, leading to a higher death rate at low agitation. The growth and death rate were correlated with a dimensionless eddy number which compares eddy forces to the buoyant force on the bead.

Physio-Microstructural Properties of Aerated Cement Slurry for Lightweight Structures

PubMed Central

Salem, Talal; Hamadna, Sameer; Darsanasiri, A. G. N. D.; Soroushian, Parviz; Balchandra, Anagi; Al-Chaar, Ghassan

2018-01-01

Cementitious composites, including ferrocement and continuous fiber reinforced cement, are increasingly considered for building construction and repair. One alternative in processing of these composites is to infiltrate the reinforcement (continuous fibers or chicken mesh) with a flowable cementitious slurry. The relatively high density of cementitious binders, when compared with polymeric binders, are a setback in efforts to introduce cementitious composites as lower-cost, fire-resistant, and durable alternatives to polymer composites. Aeration of the slurry is an effective means of reducing the density of cementitious composites. This approach, however, compromises the mechanical properties of cementitious binders. An experimental program was undertaken in order to assess the potential for production of aerated slurry with a desired balance of density, mechanical performance, and barrier qualities. The potential for nondestructive monitoring of strength development in aerated cementitious slurry was also investigated. This research produced aerated slurries with densities as low as 0.9 g/cm3 with viable mechanical and barrier qualities for production of composites. The microstructure of these composites was also investigated. PMID:29649163

Physio-Microstructural Properties of Aerated Cement Slurry for Lightweight Structures.

PubMed

Almalkawi, Areej T; Salem, Talal; Hamadna, Sameer; Darsanasiri, A G N D; Soroushian, Parviz; Balchandra, Anagi; Al-Chaar, Ghassan

2018-04-12

Cementitious composites, including ferrocement and continuous fiber reinforced cement, are increasingly considered for building construction and repair. One alternative in processing of these composites is to infiltrate the reinforcement (continuous fibers or chicken mesh) with a flowable cementitious slurry. The relatively high density of cementitious binders, when compared with polymeric binders, are a setback in efforts to introduce cementitious composites as lower-cost, fire-resistant, and durable alternatives to polymer composites. Aeration of the slurry is an effective means of reducing the density of cementitious composites. This approach, however, compromises the mechanical properties of cementitious binders. An experimental program was undertaken in order to assess the potential for production of aerated slurry with a desired balance of density, mechanical performance, and barrier qualities. The potential for nondestructive monitoring of strength development in aerated cementitious slurry was also investigated. This research produced aerated slurries with densities as low as 0.9 g/cm³ with viable mechanical and barrier qualities for production of composites. The microstructure of these composites was also investigated.

Changes in carbon and nitrogen pool during in-situ aeration of old landfills under varying conditions.

PubMed

Prantl, R; Tesar, M; Huber-Humer, M; Lechner, P

2006-01-01

Emissions from old landfills via leachate and the gas phase are influenced by state and stability of the organic matter in the solid waste and by environmental conditions within the landfill. Remediation of landfills by means of in-situ aeration is one possibility to reduce these emissions. By establishing aerobic conditions, biological processes in the landfill are accelerated. To investigate the effects of this remediation technology, lab-scale experiments with column tests have been carried out. The main goal of the present work is to characterize the changes of the carbon and nitrogen compounds in the aerated solid waste, the leachate and the gas phase under varying conditions. The results demonstrate a clear reduction of emissions and a stabilization of the organic matter. Furthermore, it is shown that both the intensity of aeration and the amount of water affect biological processes to a certain extent. Even when columns were operated under anaerobic conditions after a long running period of aeration, the emissions remained low.

Epstein-Plesset theory based measurements of concentration of nitrogen gases dissolved in aerated water

NASA Astrophysics Data System (ADS)

Sasaki, Masashi; Yamashita, Tatsuya; Ando, Keita

2016-11-01

Microbubble aeration is used to dissolved gases into water and is an important technique in agriculture and industry. We can measure concentration of dissolved oxygen (DO) in aerated water by commercial DO meters. However, there do not exist commercially available techniques to measure concentration to dissolved nitrogen (DN). In the present study, we propose the method to measure DN in aerated water with the aid of Epstein-Plesset-type analysis. Gas-supersaturated tap water is produced by applying aeration with micro-sized air bubbles and is then stored in a glass container open to the atmosphere. Diffusion-driven growth of bubbles nucleated at the container surface is recorded with a video camera. The bubble growth rate is compare to the extended Epstein-Plesset theory that models mass transfer of both DO and DN into the surface-attached bubbles base on the diffusion equation. Given the DO measurements, we can obtain the DN level by fitting in the comparison.

Effect of limited aeration on the anaerobic treatment of evaporator condensate from a sulfite pulp mill.

PubMed

Zhou, Weili; Imai, Tsuyoshi; Ukita, Masao; Li, Fusheng; Yuasa, Akira

2007-01-01

Serious inhibition was found in the regular up-flow anaerobic sludge blanket (UASB) reactor in treating the evaporator condensate from a sulfite pulp mill, which contained high strength sulfur compounds. After applying the direct limited aeration in the UASB, the inhibition was alleviated gradually and the activity of the microorganisms was recovered. The COD removal rate increased from 40% to 80% at the organic loading rate of 8kgCODm(-3)d(-1) and a hydraulic retention time of 12h. Limited aeration caused no oxygen inhibition to the anaerobic microorganisms but instigated sulfide oxidization and H(2)S removal, which was beneficial to the methanogens. The experiment confirmed the feasibility of applying limited aeration in the anaerobic reactor to alleviate the sulfide inhibition. It also proved that the anaerobic system was actually aerotolerant. SEM observation showed that the predominant microorganisms partly changed from rod-shaped methanogens to cocci after the UASB reactor was aerated.

How effective is aeration with vortex flow regulators? Pilot scale experiments

NASA Astrophysics Data System (ADS)

Wójtowicz, Patryk; Szlachta, Małgorzata

2017-11-01

Vortex flow regulators (VFR) are used in urban drainage systems as a replacement for traditional flow throttling devices. Vortex regulators are not only very efficient energy dissipators but also atomizers which are beneficial for sewer aeration. A deficit of dissolved oxygen can be a problem in both natural waters and sewerage. Hydrodynamic flow regulators can boost oxygen concentration preventing putrefaction and improving treatment of stormwater and wastewater. We were first to investigate the aeration efficiency of semi-commercial scale cylindrical vortex flow regulators to determine the potential of their application in environmental engineering and to propose modification to enhance the aeration capacity of basic designs. Different device geometries and arrangements of active outlets for both single and double discharge vortex regulators were tested in a recirculating system. In this study, we present a concise review of the current state of our extensive research on the aeration efficiency of vortex flow regulators and their application in sewerage systems.

Swelling and erosion properties of hydroxypropylmethylcellulose (Hypromellose) matrices--influence of agitation rate and dissolution medium composition.

PubMed

Kavanagh, Nicole; Corrigan, Owen I

2004-07-26

The effect of dissolution medium variables, such as medium composition, ionic strength and agitation rate, on the swelling and erosion of Hypromellose (hydroxypropylmethylcellulose, HPMC) matrices of different molecular weights was examined. Swelling and erosion of HPMC polymers was determined by measuring the wet and subsequent dry weights of matrices. It was possible to describe the rate of dissolution medium uptake in terms of a square root relationship and the erosion of the polymer in terms of the cube root law. The extent of swelling increased with increasing molecular weight, and decreased with increasing agitation rate. The erosion rate was seen to increase with decrease in polymer molecular weight, with a decrease in ionic strength and with increasing agitation rate. The sensitivity of polymer erosion to the degree of agitation may influence the ability of these polymers to give reproducible, agitation-independent release, compared to more rigid non-eroding matrix materials, in the complex hydrodynamic environment of the gastrointestinal tract.

Decreasing assault occurrence on a psychogeriatric ward: an agitation management model.

PubMed

Savage, Troy; Crawford, Ian; Nashed, Yousery

2004-05-01

An agitation management model providing staff education, quantitative assessment of agitation, and emphasized psychosocial interventions was introduced on a geriatric psychiatry ward for male patients. A within-subjects comparison was made of Cohen-Mansfield Agitation Inventory (CMAI) scores and frequency of committing assault under pre- and post-intervention conditions. Among participants (N = 8) who finished the 72-week study, CMAI scores did not differ significantly under either of the study conditions (p > .05, two-tailed t test). Twenty-nine assaults occurred during the pre-intervention time period and six assaults occurred during the post-intervention time period. According to analysis with the Wilcoxon signed ranks test, the distribution of assaults differed significantly between the two time periods (p < .05, two-tailed). Among individuals who were excluded from the intervention because of lack of consent, assaults increased over the same two time periods. Psychosocial interventions intended to reduce agitation among elderly men with dementia may not necessarily serve to decrease agitation, but may serve to decrease assault occurrence.

Effect of mixing during fermentation in yogurt manufacturing.

PubMed

Aguirre-Ezkauriatza, E J; Galarza-González, M G; Uribe-Bujanda, A I; Ríos-Licea, M; López-Pacheco, F; Hernández-Brenes, C M; Alvarez, M M

2008-12-01

In traditional yogurt manufacturing, the yogurt is not agitated during fermentation. However, stirring could be beneficial, particularly for improving heat and mass transport across the fermentation tank. In this contribution, we studied the effect of low-speed agitation during fermentation on process time, acidity profile, and microbial dynamics during yogurt fermentation in 2 laboratory-scale fermenters (3 and 5 L) with different heat-transfer characteristics. Lactobacillus bulgaricus and Streptococcus thermophilus were used as fermenting bacteria. Curves of pH, lactic acid concentration, lactose concentration, and bacterial population profiles during fermentation are presented for static and low-agitation conditions during fermentation. At low-inoculum conditions, agitation reduced the processing time by shortening the lag phase. However, mixing did not modify the duration or the shape of the pH profiles during the exponential phase. In fermentors with poor heat-transfer characteristics, important differences in microbial dynamics were observed between the agitated and nonagitated fermentation experiments; that is, agitation significantly increased the observable specific growth rate and the final microbial count of L. bulgaricus.

Cost-performance analysis of nutrient removal in a full-scale oxidation ditch process based on kinetic modeling.

PubMed

Li, Zheng; Qi, Rong; Wang, Bo; Zou, Zhe; Wei, Guohong; Yang, Min

2013-01-01

A full-scale oxidation ditch process for treating sewage was simulated with the ASM2d model and optimized for minimal cost with acceptable performance in terms of ammonium and phosphorus removal. A unified index was introduced by integrating operational costs (aeration energy and sludge production) with effluent violations for performance evaluation. Scenario analysis showed that, in comparison with the baseline (all of the 9 aerators activated), the strategy of activating 5 aerators could save aeration energy significantly with an ammonium violation below 10%. Sludge discharge scenario analysis showed that a sludge discharge flow of 250-300 m3/day (solid retention time (SRT), 13-15 days) was appropriate for the enhancement of phosphorus removal without excessive sludge production. The proposed optimal control strategy was: activating 5 rotating disks operated with a mode of "111100100" ("1" represents activation and "0" represents inactivation) for aeration and sludge discharge flow of 200 m3/day (SRT, 19 days). Compared with the baseline, this strategy could achieve ammonium violation below 10% and TP violation below 30% with substantial reduction of aeration energy cost (46%) and minimal increment of sludge production (< 2%). This study provides a useful approach for the optimization of process operation and control.

Impact of aeration disturbances on endogenous phosphorus fractions and their algae growth potential from malodorous river sediment.

PubMed

Zhu, Jin; He, Yan; Wang, Jianhua; Qiao, Zhaochao; Wang, Yi; Li, Zhihong; Huang, Minsheng

2017-03-01

The present work assessed the impact of aeration disturbances on sediment-bound phosphorus fractions and their algae growth potential from a typical malodorous river. Phosphorus was sequentially extracted by a modified version of Hedley fractionation method. It was found that the mean contents of TP was 1476.1 ± 60.3 mg/kg, consisting mainly of dilute HCl-extractable P (52.6%) and NaOH-P (19.2%). The algae growth potential tests demonstrated that algae growth had varied P-level requirements for different P speciation and NaOH-P promoted algae growth remarkably and its promoting effect was positively related to its concentration. Additionally, intermittent overlying water aeration modes were recommended, and run 1 (7.0 mg/L, 12 h) was deemed as the optimized aerated mode in terms of its relatively low ecological risk and high P retention. It was noted that NaOH-P was most affected by aeration disturbance and exhibited marked increase with the elevated dissolved oxygen (DO) level whether for intermittent overlying water or sediment aeration. This research helps to gain improved understanding of the ecological risk on sediment P, and NaOH-P is recognized as one ecologically important P fraction in the sediments considering its relatively high proportion and bioavailability.

Influence of Concentration and Agitation of Sodium Hypochlorite and Peracetic Acid Solutions on Tissue Dissolution.

PubMed

Tanomaru-Filho, Mário; Silveira, Bruna Ramos Franco; Martelo, Roberta Bosso; Guerreiro-Tanomaru, Juliane Maria

2015-11-01

To evaluated the tissue dissolution of sodium hypochlorite (NaOCl) and peracetic acid (PA) solutions at different concentrations, with or without ultrasonic agitation. The following solutions were analyzed: 2.5% NaOCl, 0.5, 1 and 2% PA, 1% PA associated with 6.5% hydrogen peroxide (HP) and saline. Fragments of bovine pulp tissue with 25 ± 2g mg were immersed into test tubes containing 4 mL of the solutions for 10 minutes. In the groups with agitation, pulp tissues were submitted to 2 cycles of 1 minute of ultrasonic agitation. The specimens were weighed after the removal from the solutions. The percentage of mass loss was calculated according to the difference of mass before and after exposure to solutions. Data were submitted to ANOVA and Tukey tests (p < 0.05). A total of 2.5% NaOCl with or without agitation showed the higher tissue dissolution (between 64.5 and 67% of mass reduction) (p < 0.005). By comparing the PA solutions, the concentrations of 1 and 2% with or without agitation and the concentration of 0.5% with agitation showed similar dissolution activity (between 35.4 and 44% of mass reduction). The use of the ultrasonic agitation promoted an increase of the dissolution ability only for 0.5% PA. Peracetic acid solution has pulp tissue dissolution. However, this ability is lower than 2.5% NaOCl solution. The sodium hypochlorite solution shows higher ability to dissolve tissue than PA.

Efficacy and safety of valproic acid versus haloperidol in patients with acute agitation: results of a randomized, double-blind, parallel-group trial.

PubMed

Asadollahi, Shadi; Heidari, Kamran; Hatamabadi, Hamidreza; Vafaee, Reza; Yunesian, Somayeh; Azadbakht, Alireza; Mirmohseni, Ladan

2015-05-01

The objective of this study was to compare the efficacy of valproate versus haloperidol in decreasing the agitation level in affected patients in the emergency department. We assigned 80 acutely agitated patients to receive either intravenous sodium valproate (20 mg/kg) or intramuscular haloperidol (5 mg/1 ml). Agitation was measured at baseline and 30 min after the first injection using the Agitation-Calmness Evaluation Scale (ACES), the Positive and Negative Syndrome Scale-Excited Component subscale, and the Agitated Behavior Scale. For 80 patients treated with sodium valproate, the mean ± SD dosage was 1541.5 ± 286 mg (range 940-2400). The mean postintervention ACES scores from baseline to 30 min after drug injection were 4.73 (SD = 1.93) for the valproate group and 5.45 (SD = 2.09) for the haloperidol group (P = 0.028). No significant differences were observed in terms of the mean changes 30 min after the intervention for two additional agitation scales. A larger proportion of patients in the haloperidol group experienced intense sedation (36.2%, P < 0.001) and extrapyramidal symptoms (8.7%, P = 0.007) compared with the valproate group (2.5% for intense sedation, no patient for extrapyramidal symptoms). The findings suggest that in the clinical practice setting of emergency psychiatry, intravenous valproate is as effective as haloperidol in reducing agitation, with a better safety profile.

A triple fouling layers perspective on evaluation of membrane fouling under different scenarios of membrane bioreactor operation

PubMed Central

2014-01-01

One of the main factors affecting membrane fouling in MBRs is operational conditions. In this study the influence of aeration rate, filtration mode, and SRT on hollow fiber membrane fouling was investigated using a triple fouling layers perspective. The sludge microbial population distribution was also determined by PCR method. Through various applied operational scenarios the optimal conditions were: aeration rate of 15 LPM; relaxation mode with 40s duration and 8 min. interval; and SRT of 30 days. The similarity between SMP variations in triple fouling layers with its corresponding hydraulic resistance confirmed the effect of SMP on membrane fouling. Among three fouling fractions, the upper (rinsed) layer found to have the most effect on membrane fouling which implies the critical role of aeration, but as for multilateral effects of aeration, the optimal aeration rate should be determined more precisely. Relaxation interval was more effective than its duration for fouling control. SRT variations in addition to influencing the amount of SMP, also affect on the structure of these material. At longer SRTs (20, 30 days) a greater percentage of SMP could penetrate into the membrane pores and for shorter SRTs they accumulate more on membrane surface. Results showed that there is a very good correlation between total hydraulic resistance (Log R) and protein to carbohydrate ratio at the rinsed layer (P1/C1). Considering significant effects of aeration and SRT conditions on this ratio (according to data), it is very determinative to apply the optimal aeration and SRT conditions. PMID:25002969

Characterization of the external and internal flow structure of an aerated-liquid injector using X-ray radiography and fluorescence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peltier, Scott J.; Lin, Kuo-Cheng; Carter, Campbell D.

In the present study, the internal flowfield of aerated-liquid fuel injectors is examined through x-ray radiography and x-ray fluorescence. An inside-out injector, consisting of a perforated aerating tube within an annular liquid stream, sprays into a quiescent environment at a fixed mass flow rate of water and nitrogen gas. The liquid is doped with bromine (in the form of NaBr) to create an x-ray fluorescence signal. This allows for reasonable absorption and fluorescence signals, and one or both diagnostics can be used to track the liquid distribution. The injector housing is fabricated from beryllium (Be), which allows the internal flowfieldmore » to be examined (as Be has relatively low x-ray attenuation coefficient). Two injector geometries are compared, illustrating the effects of aerating orifice size and location on the flow evolution. Time-averaged equivalent pathlength (EPL) and line-of-sight averaged density ρ(y) reveal the formation of the two-phase mixture, showing that the liquid film thickness along the injector walls is a function of the aerating tube geometry, though only upstream of the nozzle. These differences in gas and liquid distribution (between injectors with different aerating tube designs) are suppressed as the mixture traverses the nozzle contraction. The averaged liquid velocity (computed from the density and liquid mass flow rate) reveal a similar trend. This suggests that at least for the current configurations, the plume width, liquid mass distribution, and averaged liquid velocity for the time-averaged external spray are insensitive to the aerating tube geometry.« less

Simultaneous nitrification, denitrification, and phosphorus removal in single-tank low-dissolved-oxygen systems under cyclic aeration.

PubMed

Ju, Lu-Kwang; Huang, Lin; Trivedi, Hiren

2007-08-01

Simultaneous nitrification and denitrification (SND or SNdN) may occur at low dissolved oxygen concentrations. In this study, bench-scale (approximately 6 L) bioreactors treating a continuous feed of synthetic wastewater were used to evaluate the effects of solids retention time and low dissolved oxygen concentration, under cyclic aeration, on the removal of organics, nitrogen, and phosphorus. The cyclic aeration was carried out with repeated cycles of 1 hour at a higher dissolved oxygen concentration (HDO) and 30 minutes at a lower (or zero) dissolved oxygen concentration (LDO). Compared with aeration at constant dissolved oxygen concentrations, the cyclic aeration, when operated with proper combinations of HDO and LDO, produced better-settling sludge and more complete nitrogen and phosphorus removal. For nitrogen removal, the advantage resulted from the more readily available nitrate and nitrite (generated by nitrification during the HDO period) for denitrification (during the LDO period). For phosphorus removal, the advantage of cyclic aeration came from the development of a higher population of polyphosphate-accumulating organisms, as indicated by the higher phosphorus contents in the sludge solids of the cyclically aerated systems. Nitrite shunt was also observed to occur in the LDO systems. Higher ratios of nitrite to nitrate were found in the systems of lower HDO (and, to less dependency, higher LDO), suggesting that the nitrite shunt took place mainly because of the disrupted nitrification at lower HDO. The study results indicated that the HDO used should be kept reasonably high (approximately 0.8 mg/L) or the HDO period prolonged, to promote adequate nitrification, and the LDO kept low (< or =0.2 mg/L), to achieve more complete denitrification and higher phosphorus removal. The above findings in the laboratory systems find strong support from the results obtained in full-scale plant implementation. Two plant case studies using the cyclic low-dissolved-oxygen aeration for creating and maintaining SND are also presented.

A comparative study of leachate quality and biogas generation in simulated anaerobic and hybrid bioreactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Qiyong; Tian, Ying; Wang, Shen

2015-07-15

Highlights: • Temporary aeration shortened the initial acid inhibition phase for methanogens. • COD decreased faster in the hybrid bioreactor than that in the anaerobic control. • Methane generations from hybrid bioreactors were 133.4 L/kg{sub vs} and 113.2 L/kg{sub vs}. • MSW settlement increased with increasing the frequency of intermittent aeration. - Abstract: Research has been conducted to compare leachate characterization and biogas generation in simulated anaerobic and hybrid bioreactor landfills with typical Chinese municipal solid waste (MSW). Three laboratory-scale reactors, an anaerobic (A1) and two hybrid bioreactors (C1 and C2), were constructed and operated for about 10 months. Themore » hybrid bioreactors were operated in an aerobic–anaerobic mode with different aeration frequencies by providing air into the upper layer of waste. Results showed that the temporary aeration into the upper layer aided methane generation by shortening the initial acidogenic phase because of volatile fatty acids (VFAs) reduction and pH increase. Chemical oxygen demand (COD) decreased faster in the hybrid bioreactors, but the concentrations of ammonia–nitrogen in the hybrid bioreactors were greater than those in the anaerobic control. Methanogenic conditions were established within 75 d and 60 d in C1 and C2, respectively. However, high aeration frequency led to the consumption of organic matters by aerobic degradation and resulted in reducing accumulative methane volume. The temporary aeration enhanced waste settlement and the settlement increased with increasing the frequency of aeration. Methane production was inhibited in the anaerobic control; however, the total methane generations from hybrid bioreactors were 133.4 L/kg{sub vs} and 113.2 L/kg{sub vs}. As for MSW with high content of food waste, leachate recirculation right after aeration stopped was not recommended due to VFA inhibition for methanogens.« less

40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure..., pressure relief devices in light liquid or heavy liquid service, and instrumentation systems shall be...

40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure..., pressure relief devices in light liquid or heavy liquid service, and instrumentation systems shall be...

40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure..., pressure relief devices in light liquid or heavy liquid service, and instrumentation systems shall be...

40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2012 CFR

2012-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2014 CFR

2014-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2013 CFR

2013-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

Code of Federal Regulations, 2012 CFR

2012-07-01

..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure..., pressure relief devices in light liquid or heavy liquid service, and instrumentation systems shall be...

System for agitating the acid in a lead-acid battery

DOEpatents

Weintraub, Alvin; MacCormack, Robert S.

1987-01-01

A system and method for agitating the acid in a large lead-sulfuric acid storage battery of the calcium type. An air-lift is utilized to provide the agitation. The air fed to the air-lift is humidified prior to being delivered to the air-lift.

40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2010 CFR

2010-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

Waiting room crowding and agitation in a dedicated psychiatric emergency service.

PubMed

El-Mallakh, Rif S; Whiteley, Amanda; Wozniak, Tanya; Ashby, McCray; Brown, Shawn; Colbert-Trowel, Danya; Pennington, Tammy; Thompson, Michael; Tasnin, Rokeya; Terrell, Christina L

2012-05-01

Emergency department crowding is a growing problem that impacts patient care and safety. The effect of crowding has not been examined in emergency psychiatric services. The association between patient census and use of restraints, seclusion, and anti-agitation medications as needed was examined for 1 month. A total of 689 patients were seen in 31 days. The average hourly census was 6.8 ± 2.8 (range 0 to 18). There were 33 incidences of seclusion or restraint and an additional 15 instances of medications administered for agitation. The use of seclusion, restraint, or medication for agitation was significantly associated with census (r2 = 0.3, F = 5.47, P = .036). Crowding in emergency psychiatric waiting rooms may increase the need for seclusion, restraint, or medications for agitation.

Perioperative prediction of agitated (hyperactive) delirium after cardiac surgery in adults - The development of a practical scorecard.

PubMed

Mufti, Hani N; Hirsch, Gregory M

2017-12-01

Delirium is a temporary mental disorder that occurs frequently among hospitalized patients. In this study we sought to develop a user-friendly scorecard based on perioperative features to identify patients at risk of developing agitated delirium after cardiac surgery. Retrospective analysis was performed on adult patients undergoing cardiac surgery in a single center. A parsimonious predictive model was created, with subsequent internal validation. Then a simple scorecard was developed that can be used to predict the probability of agitated delirium. Among the 5584 patients who met the study criteria, 614 (11.4%) developed postoperative agitated delirium. Independent predictors of postoperative agitated delirium were age, male gender, history of cerebrovascular disease, procedure other than isolated Coronary Arteries Bypass Surgery, transfusion of blood products within the first 48h, mechanical ventilation for >24h, length of stay in the Intensive Care Unit. The scorecard stratified patients into 4 categories at risk of postoperative agitated delirium ranging from <5% to >30%. Using a large cohort of adult patient's undergoing cardiac surgery, a user-friendly scorecard was developed and validated, which will facilitate the implementation of timely interventions to mitigate adverse effects of agitated delirium in this high risk population. Copyright © 2017 Elsevier Inc. All rights reserved.

Computational fluid dynamics (CFD) insights into agitation stress methods in biopharmaceutical development.

PubMed

Bai, Ge; Bee, Jared S; Biddlecombe, James G; Chen, Quanmin; Leach, W Thomas

2012-02-28

Agitation of small amounts of liquid is performed routinely in biopharmaceutical process, formulation, and packaging development. Protein degradation commonly results from agitation, but the specific stress responsible or degradation mechanism is usually not well understood. Characterization of the agitation stress methods is critical to identifying protein degradation mechanisms or specific sensitivities. In this study, computational fluid dynamics (CFD) was used to model agitation of 1 mL of fluid by four types of common laboratory agitation instruments, including a rotator, orbital shaker, magnetic stirrer and vortex mixer. Fluid stresses in the bulk liquid and near interfaces were identified, quantified and compared. The vortex mixer provides the most intense stresses overall, while the stir bar system presented locally intense shear proximal to the hydrophobic stir bar surface. The rotator provides gentler fluid stresses, but the air-water interfacial area and surface stresses are relatively high given its low rotational frequency. The orbital shaker provides intermediate-level stresses but with the advantage of a large stable platform for consistent vial-to-vial homogeneity. Selection of experimental agitation methods with targeted types and intensities of stresses can facilitate better understanding of protein degradation mechanisms and predictability for "real world" applications. Copyright © 2011 Elsevier B.V. All rights reserved.

Silicone Oil- and Agitation-Induced Aggregation of a Monoclonal Antibody in Aqueous Solution

PubMed Central

Thirumangalathu, Renuka; Krishnan, Sampathkumar; Ricci, Margaret Speed; Brems, David N.; Randolph, Theodore W.; Carpenter, John F.

2009-01-01

Silicone oil, which is used as a lubricant or coating in devices such as syringes, needles and pharmaceutical containers, has been implicated in aggregation and particulation of proteins and antibodies. Aggregation of therapeutic protein products induced by silicone oil can pose a challenge to their development and commercialization. To systematically characterize the role of silicone oil on protein aggregation, the effects of agitation, temperature, pH and ionic strength on silicone oil-induced loss of monomeric anti-streptavidin IgG 1 antibody were examined. Additionally, the influences of excipients polysorbate20 and sucrose on protein aggregation were investigated. In the absence of agitation, protein absorbed to silicone oil with approximately monolayer coverage, however silicone oil did not stimulate aggregation during isothermal incubation unless samples were also agitated. A synergistic stimulation of aggregation by a combination of agitation and silicone oil was observed. Solution conditions which reduced colloidal stability of the antibody, as assessed by determination of osmotic second virial coefficients, accelerated aggregation during agitation with silicone oil. Polysorbate20 completely inhibited silicone oil-induced monomer loss during agitation. A formulation strategy optimizing colloidal stability of the antibody as well as incorporation of surfactants such as polysorbate20 is proposed to reduce silicone oil-induced aggregation of therapeutic protein products. PMID:19360857

Prehospital Agitation and Sedation Trial (PhAST): A Randomized Control Trial of Intramuscular Haloperidol versus Intramuscular Midazolam for the Sedation of the Agitated or Violent Patient in the Prehospital Environment.

PubMed

Isenberg, Derek L; Jacobs, Dorian

2015-10-01

Violent patients in the prehospital environment pose a threat to health care workers tasked with managing their medical conditions. While research has focused on methods to control the agitated patient in the emergency department (ED), there is a paucity of data looking at the optimal approach to subdue these patients safely in the prehospital setting. Hypothesis This study evaluated the efficacy of two different intramuscular medications, midazolam and haloperidol, to determine their efficacy in sedating agitated patients in the prehospital setting. This was a prospective, randomized, observational trial wherein agitated patients were administered intramuscular haloperidol or intramuscular midazolam to control agitation. Agitation was quantified by the Richmond Agitation and Sedation Scale (RASS). Paramedics recorded the RASS and vital signs every five minutes during transport and again upon arrival to the ED. The primary outcome was mean time to achieve a RASS less than +1. Secondary outcomes included mean time for patients to return to baseline mental status and adverse events. Five patients were enrolled in each study group. In the haloperidol group, the mean time to achieve a RASS score of less than +1 was 24.8 minutes (95% CI, 8-49 minutes), and the mean time for the return of a normal mental status was 84 minutes (95% CI, 0-202 minutes). Two patients required additional prehospital doses for adequate sedation. There were no adverse events recorded in the patients administered haloperidol. In the midazolam group, the mean time to achieve a RASS score of less than +1 was 13.5 minutes (95% CI, 8-19 minutes) and the mean time for the return of normal mental status was 105 minutes (95% CI, 0-178 minutes). One patient required additional sedation in the ED. There were no adverse events recorded among the patients administered midazolam. Midazolam and haloperidol administered intramuscularly appear equally effective for sedating an agitated patient in the prehospital setting. Midazolam appears to have a faster onset of action, as evidenced by the shorter time required to achieve a RASS score of less than +1 in the patients who received midazolam. Haloperidol offers an alternative option for the sedation of an agitated patient. Further studies should focus on continued investigation into appropriate sedation of agitated patients in the prehospital setting.

GROUT HOPPER MODELING STUDY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, S.

2011-08-30

The Saltstone facility has a grout hopper tank to provide agitator stirring of the Saltstone feed materials. The tank has about 300 gallon capacity to provide a larger working volume for the grout slurry to be held in case of a process upset, and it is equipped with a mechanical agitator, which is intended to keep the grout in motion and agitated so that it won't start to set up. The dry feeds and the salt solution are already mixed in the mixer prior to being transferred to the hopper tank. The hopper modeling study through this work will focusmore » on fluid stirring and agitation, instead of traditional mixing in the literature, in order to keep the tank contents in motion during their residence time so that they will not be upset or solidified prior to transferring the grout to the Saltstone disposal facility. The primary objective of the work is to evaluate the flow performance for mechanical agitators to prevent vortex pull-through for an adequate stirring of the feed materials and to estimate an agitator speed which provides acceptable flow performance with a 45{sup o} pitched four-blade agitator. In addition, the power consumption required for the agitator operation was estimated. The modeling calculations were performed by taking two steps of the Computational Fluid Dynamics (CFD) modeling approach. As a first step, a simple single-stage agitator model with 45{sup o} pitched propeller blades was developed for the initial scoping analysis of the flow pattern behaviors for a range of different operating conditions. Based on the initial phase-1 results, the phase-2 model with a two-stage agitator was developed for the final performance evaluations. A series of sensitivity calculations for different designs of agitators and operating conditions have been performed to investigate the impact of key parameters on the grout hydraulic performance in a 300-gallon hopper tank. For the analysis, viscous shear was modeled by using the Bingham plastic approximation. Steady state analyses with a two-equation turbulence model were performed with the FLUENT{trademark} codes. All analyses were based on three-dimensional results. Recommended operational guidance was developed by using the basic concept that local shear rate profiles and flow patterns can be used as a measure of hydraulic performance and spatial stirring. Flow patterns were estimated by a Lagrangian integration technique along the flow paths from the material feed inlet. The modeling results show that when the two-stage agitator consisting of a 45{sup o} pitched propeller and radial flat-plate blades is run at 140 rpm speed with 28 in diameter, the agitator provides an adequate stirring of the feed materials for a wide range of yield stresses (1 to 21 Pa) and the vortex system is shed into the remote region of the tank boundary by the blade passage in an efficient way. The results of this modeling study were used to develop the design guidelines for the agitator stirring and dispersion of the Saltstone feed materials in a hopper tank.« less

Prevalence of and associations with agitation in residents with dementia living in care homes: MARQUE cross-sectional study.

PubMed

Livingston, Gill; Barber, Julie; Marston, Louise; Rapaport, Penny; Livingston, Deborah; Cousins, Sian; Robertson, Sarah; La Frenais, Francesca; Cooper, Claudia

2017-07-01

Agitation is reportedly the most common neuropsychiatric symptom in care home residents with dementia. To report, in a large care home survey, prevalence and determinants of agitation in residents with dementia. We interviewed staff from 86 care homes between 13 January 2014 and 12 November 2015 about residents with dementia with respect to agitation (Cohen-Mansfield Agitation Inventory (CMAI)), quality of life (DEMQOL-proxy) and dementia severity (Clinical Dementia Rating). We also interviewed residents and their relatives. We used random effects models adjusted for resident age, gender, dementia severity and care home type with CMAI as a continuous score. Out of 3053 (86.2%) residents who had dementia, 1489 (52.7%) eligible residents participated. Fifteen per cent of residents with very mild dementia had clinically significant agitation compared with 33% with mild (odds ratios (ORs)=4.49 95% confidence interval (CI)=2.30) and 45% with moderate or severe dementia (OR=6.95 95% CI=3.63, 13.31 and OR=6.23 95% CI=3.25, 11.94, respectively). More agitation was associated with lower quality of life (regression coefficient (rc)=-0.53; 95% CI=-0.61, -0.46) but not with staffing or resident ratio (rc=0.03; 95% CI=-0.04, 0.11), level of residents' engagement in home activities (rc=3.21; 95% CI=-0.82, 7.21) or family visit numbers (rc=-0.03; 95% CI=-0.15, 0.08). It was correlated with antipsychotic use (rc=6.45; 95% CI=3.98, 8.91). Care home residents with dementia and agitation have lower quality of life. More staffing time and activities as currently provided are not associated with lower agitation levels. New approaches to develop staff skills in understanding and responding to the underlying reasons for individual resident's agitation require development and testing. None. © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license.

Prevalence of and associations with agitation in residents with dementia living in care homes: MARQUE cross-sectional study

PubMed Central

Barber, Julie; Marston, Louise; Rapaport, Penny; Livingston, Deborah; Cousins, Sian; Robertson, Sarah; La Frenais, Francesca; Cooper, Claudia

2017-01-01

Background Agitation is reportedly the most common neuropsychiatric symptom in care home residents with dementia. Aims To report, in a large care home survey, prevalence and determinants of agitation in residents with dementia. Method We interviewed staff from 86 care homes between 13 January 2014 and 12 November 2015 about residents with dementia with respect to agitation (Cohen-Mansfield Agitation Inventory (CMAI)), quality of life (DEMQOL-proxy) and dementia severity (Clinical Dementia Rating). We also interviewed residents and their relatives. We used random effects models adjusted for resident age, gender, dementia severity and care home type with CMAI as a continuous score. Results Out of 3053 (86.2%) residents who had dementia, 1489 (52.7%) eligible residents participated. Fifteen per cent of residents with very mild dementia had clinically significant agitation compared with 33% with mild (odds ratios (ORs)=4.49 95% confidence interval (CI)=2.30) and 45% with moderate or severe dementia (OR=6.95 95% CI=3.63, 13.31 and OR=6.23 95% CI=3.25, 11.94, respectively). More agitation was associated with lower quality of life (regression coefficient (rc)=−0.53; 95% CI=−0.61, −0.46) but not with staffing or resident ratio (rc=0.03; 95% CI=−0.04, 0.11), level of residents’ engagement in home activities (rc=3.21; 95% CI=−0.82, 7.21) or family visit numbers (rc=−0.03; 95% CI=−0.15, 0.08). It was correlated with antipsychotic use (rc=6.45; 95% CI=3.98, 8.91). Conclusions Care home residents with dementia and agitation have lower quality of life. More staffing time and activities as currently provided are not associated with lower agitation levels. New approaches to develop staff skills in understanding and responding to the underlying reasons for individual resident’s agitation require development and testing. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license. PMID:28794896

Effects of agitation on particle-size distribution and enzymatic hydrolysis of pretreated spruce and giant reed.

PubMed

Kadić, Adnan; Palmqvist, Benny; Lidén, Gunnar

2014-01-01

Mixing is an energy demanding process which has been previously shown to affect enzymatic hydrolysis. Concentrated biomass slurries are associated with high and non-Newtonian viscosities and mixing in these systems is a complex task. Poor mixing can lead to mass and/or heat transfer problems as well as inhomogeneous enzyme distribution, both of which can cause possible yield reduction. Furthermore the stirring energy dissipation may impact the particle size which in turn may affect the enzymatic hydrolysis. The objective of the current work was to specifically quantify the effects of mixing on particle-size distribution (PSD) and relate this to changes in the enzymatic hydrolysis. Two rather different materials were investigated, namely pretreated Norway spruce and giant reed. Changes in glucan hydrolysis and PSD were measured as a function of agitation during enzymatic hydrolysis at fiber loadings of 7 or 13% water-insoluble solids (WIS). Enzymatic conversion of pretreated spruce was strongly affected by agitation rates at the higher WIS content. However, at low WIS content the agitation had almost no effect on hydrolysis. There was some effect of agitation on the hydrolysis of giant reed at high WIS loading, but it was smaller than that for spruce, and there was no measurable effect at low WIS loading. In the case of spruce, intense agitation clearly affected the PSD and resulted in a reduced mean particle size, whereas for giant reed the decrease in particle size was mainly driven by enzymatic action. However, the rate of enzymatic hydrolysis was not increased after size reduction by agitation. The impact of agitation on the enzymatic hydrolysis clearly depends not only on feedstock but also on the solids loading. Agitation was found to affect the PSD differently for the examined pretreated materials spruce and giant reed. The fact that the reduced mean particle diameter could not explain the enhanced hydrolysis rates found for spruce at an elevated agitation suggests that mass transfer at sustained high viscosities plays an important role in determining the rate of enzymatic hydrolysis.

Automatic quantitative computed tomography segmentation and analysis of aerated lung volumes in acute respiratory distress syndrome-A comparative diagnostic study.

PubMed

Klapsing, Philipp; Herrmann, Peter; Quintel, Michael; Moerer, Onnen

2017-12-01

Quantitative lung computed tomographic (CT) analysis yields objective data regarding lung aeration but is currently not used in clinical routine primarily because of the labor-intensive process of manual CT segmentation. Automatic lung segmentation could help to shorten processing times significantly. In this study, we assessed bias and precision of lung CT analysis using automatic segmentation compared with manual segmentation. In this monocentric clinical study, 10 mechanically ventilated patients with mild to moderate acute respiratory distress syndrome were included who had received lung CT scans at 5- and 45-mbar airway pressure during a prior study. Lung segmentations were performed both automatically using a computerized algorithm and manually. Automatic segmentation yielded similar lung volumes compared with manual segmentation with clinically minor differences both at 5 and 45 mbar. At 5 mbar, results were as follows: overdistended lung 49.58mL (manual, SD 77.37mL) and 50.41mL (automatic, SD 77.3mL), P=.028; normally aerated lung 2142.17mL (manual, SD 1131.48mL) and 2156.68mL (automatic, SD 1134.53mL), P = .1038; and poorly aerated lung 631.68mL (manual, SD 196.76mL) and 646.32mL (automatic, SD 169.63mL), P = .3794. At 45 mbar, values were as follows: overdistended lung 612.85mL (manual, SD 449.55mL) and 615.49mL (automatic, SD 451.03mL), P=.078; normally aerated lung 3890.12mL (manual, SD 1134.14mL) and 3907.65mL (automatic, SD 1133.62mL), P = .027; and poorly aerated lung 413.35mL (manual, SD 57.66mL) and 469.58mL (automatic, SD 70.14mL), P=.007. Bland-Altman analyses revealed the following mean biases and limits of agreement at 5 mbar for automatic vs manual segmentation: overdistended lung +0.848mL (±2.062mL), normally aerated +14.51mL (±49.71mL), and poorly aerated +14.64mL (±98.16mL). At 45 mbar, results were as follows: overdistended +2.639mL (±8.231mL), normally aerated 17.53mL (±41.41mL), and poorly aerated 56.23mL (±100.67mL). Automatic single CT image and whole lung segmentation were faster than manual segmentation (0.17 vs 125.35seconds [P<.0001] and 10.46 vs 7739.45seconds [P<.0001]). Automatic lung CT segmentation allows fast analysis of aerated lung regions. A reduction of processing times by more than 99% allows the use of quantitative CT at the bedside. Copyright © 2016 Elsevier Inc. All rights reserved.

Polyhydroxyalkanoate synthesis by mixed microbial consortia cultured on fermented dairy manure: Effect of aeration on process rates/yields and the associated microbial ecology.

PubMed

Coats, Erik R; Watson, Benjamin S; Brinkman, Cynthia K

2016-12-01

Polyhydroxyalkanoates (PHAs) are biodegradable polymers that can substitute for petroleum-based plastics in a variety of applications. One avenue to commercial PHA production involves coupling waste-based synthesis with the use of mixed microbial consortia (MMC). In this regard, production requires maximizing the enrichment of a MMC capable of feast-famine PHA synthesis, with the metabolic response induced through imposition of aerobic-dynamic feeding (ADF) conditions. However, the concept of PHA production in complex matrices remains unrefined; process operational improvements are needed, along with an enhanced understanding of the MMC. Research presented herein investigated the effect of aeration on feast-famine PHA synthesis, with four independent aeration state systems studied; MMC were fed volatile fatty acid (VFA)-rich fermented dairy manure. Regardless of the aeration state, all MMC exhibited a feast-famine response based on observed carbon cycling. Moreover, there was no statistical difference in PHA synthesis rates, with q PHA ranging from 0.10 to 0.19 CmmolPHA gVSS -1 min -1 ; VFA uptake rates exhibited similar statistical indifferences. PHA production assessments on the enriched MMC resulted in maximum intracellular concentrations ranging from 22.5 to 90.7% (mgPHA mgVSS -1 ); at maximum concentration, the mean hydroxyvalerate mol content was 73 ± 0.6%. While a typical feast-famine dissolved oxygen (DO) pattern was observed at maximum aeration, less resolution was observed at decreasing aeration rates, suggesting that DO may not be an optimal process monitoring parameter. At lower aeration states, nitrogen cycling patterns, supported by molecular investigations targeting AOBs and NOBs, indicate that NO 2 and NO 3 sustained feast-famine PHA synthesis. Next-generation sequencing analysis of the respective MMC revealed numerous and diverse genera exhibiting the potential to achieve PHA synthesis, suggesting functional redundancy embedded in the diverse MMC. Ultimately, results demonstrate that aeration can be controlled in waste-based ADF systems to sustain PHA production potential, while enriching for a diverse MMC that exhibits potential functional redundancy. Reduced aeration could also enhance cost competitiveness of waste-based PHA production, with potential further benefits associated with nitrogen treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Long term care staff beliefs about evidence based practices for the management of dementia and agitation.

PubMed

Ayalon, Liat; Arean, Patricia; Bornfeld, Heather; Beard, Renee

2009-02-01

Despite a growing literature on effective interventions for Alzheimer's disease (AD) and agitation, the management of these conditions in long term care (LTC) often is inadequate. The goals of the present study were: (a) to evaluate existing beliefs about evidence based practices (EBP) for the management of Alzheimer's disease and agitation among LTC staff; and (b) to evaluate the contribution of demographic and attitudinal variables to LTC staff beliefs about these EBP. A cross sectional study of 371 LTC staff members completed an EBP questionnaire, a short demographic questionnaire, and an attitudinal questionnaire about AD and agitation. Paraprofessional caregivers, those of lower educational level, and ethnic minorities were more likely to be in disagreement with the EBP views examined in this study. Those in disagreement with the EBP views also reported a preference towards not working with residents with AD and agitation and a sense of helplessness associated with such work. Disagreement with EBP views was associated with both normalization and stigmatization of AD and agitation. Paraprofessional caregivers, ethnic minorities, and people of lower educational level are most at need for educational activities about AD and neuropsychiatric symptoms. Educational efforts geared towards changing the belief system of LTC staff should target not only EBP but also information about AD and agitation as conditions that are deviant from the normal aging process, yet non-stigmatizing. It is expected that following EBP will empower staff and improve staff motivation to work with residents with AD and agitation. (c) 2008 John Wiley & Sons, Ltd.

Effect of calcium oxide (CaO) and sawdust on adhesion and cohesion characteristics of sewage sludge under agitated and non-agitated drying conditions.

PubMed

Deng, Wen-Yi; Yuan, Min-Hao; Mei, Jing; Liu, Ya-Jun; Su, Ya-Xin

2017-03-01

Stickiness phenomenon is widely observed in sewage sludge drying practices. This paper is aimed at demonstrating and comparing the sticky properties of sewage sludge through non-agitated and agitated drying tests specially designed for sewage sludge. Special attentions were paid to the effects of additives, i.e. CaO, fine sawdust (FSD) and coarse sawdust (CSD), on the adhesive and cohesive characteristics of sewage sludge. The results indicated that the sticky properties of the sludge were markedly different under the different testing methods, and was also greatly influenced by CaO or sawdust addition. For instance, in the non-agitated drying tests, CaO can significantly enhance the maximum adhesive and cohesive stresses of the sludge, whereas in the agitated drying tests, the torque of agitation, which strongly correlated with the cohesive stress of the sludge, was lowered by CaO addition. During agitated drying process, sludge lump with CaO addition started to break up at higher moisture content than that of original sludge. On the other hand, sawdust also affected the sticky properties of sludge in a way that was totally different with CaO. After sawdust addition (at 5-10%WS (wet sludge basis)), the cohesive stress of the sludge was markedly increased due to strengthening of mechanical interlocking inside the sludge, whereas the adhesiveness of the sludge was lowered by sawdust addition. The influencing mechanisms of CaO and sawdust under the different testing methods were detailedly discussed in the paper. Copyright © 2016 Elsevier Ltd. All rights reserved.

Use of preferred music to decrease agitated behaviours in older people with dementia: a review of the literature.

PubMed

Sung, Huei-Chuan; Chang, Anne M

2005-10-01

This paper reviews study findings of preferred music on agitated behaviours for older people with dementia and provides implications for future research and practice. Music has been suggested as a feasible and less costly intervention to manage agitated behaviours in older people with dementia. However, no review of the literature focusing on study findings of preferred music on agitated behaviours in older people with dementia had been reported. A review was undertaken using electronic databases with specified search terms for the period of 1993-2005. The references listed in the publications selected were also searched for additional studies. Eight research-based articles met the inclusion criteria and were included in the review. The preferred music intervention demonstrated positive outcomes in reducing the occurrence of some types of agitated behaviours in older people with dementia. The findings from these studies were relatively consistent in finding improvement in agitated behaviours although the findings in one study did not reach statistical significance. The small sample sizes and some variations in the application of the preferred music intervention mean that caution is needed in drawing conclusions from these studies. This review highlights that preferred music has positive effects on decreasing agitated behaviours in older people with dementia; however, the methodological limitations indicate the need for further research. Findings from the review highlight the beneficial outcomes of preferred music in reducing agitated behaviours for older people with dementia. The incorporation of preferred music has the potential to provide a therapeutic approach to the care of older people with dementia.

Effect of dexmedetomidine on preventing agitation and delirium after microvascular free flap surgery: a randomized, double-blind, control study.

PubMed

Yang, Xudong; Li, Zhenzhen; Gao, Chunyan; Liu, Ruichang

2015-06-01

To determine whether dexmedetomidine sedation in the postanesthesia care unit (PACU) could decrease agitation and delirium after free flap surgery. Eighty patients were randomly divided into 2 groups. In the experimental group, dexmedetomidine was given at an hourly infusion rate of 0.5 μg/kg for 1 hour before the operation was completed and continued in the PACU at 0.2 to 0.7 μg/kg continuously until the next morning. In the control group, normal saline was given during the same periods. Patients in the 2 groups received sufentanil and midazolam for sedation and pain relief when necessary. Agitation was monitored with the Riker Sedation-Agitation Scale in the PACU and delirium was monitored with the Confusion Assessment Method for the Intensive Care Unit for 5 days postoperatively. The overall incidence of agitation was similar between the 2 groups. However, when the influence of patient shifting was excluded, the incidence of agitation in the dexmedetomidine group was apparently lower than that in the control group (10.3 vs 30%; P = .029). No difference was found in the occurrence of delirium between the experimental and control groups (5.1 vs 12.5%; P = .432). Dexmedetomidine does not change the overall incidence of agitation after free flap surgery; however, it does decrease agitation after PACU admission. It does not prevent delirium within 5 days postoperatively. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

CFD simulation of local and global mixing time in an agitated tank

NASA Astrophysics Data System (ADS)

Li, Liangchao; Xu, Bin

2017-01-01

The Issue of mixing efficiency in agitated tanks has drawn serious concern in many industrial processes. The turbulence model is very critical to predicting mixing process in agitated tanks. On the basis of computational fluid dynamics(CFD) software package Fluent 6.2, the mixing characteristics in a tank agitated by dual six-blade-Rushton-turbines(6-DT) are predicted using the detached eddy simulation(DES) method. A sliding mesh(SM) approach is adopted to solve the rotation of the impeller. The simulated flow patterns and liquid velocities in the agitated tank are verified by experimental data in the literature. The simulation results indicate that the DES method can obtain more flow details than Reynolds-averaged Navier-Stokes(RANS) model. Local and global mixing time in the agitated tank is predicted by solving a tracer concentration scalar transport equation. The simulated results show that feeding points have great influence on mixing process and mixing time. Mixing efficiency is the highest for the feeding point at location of midway of the two impellers. Two methods are used to determine global mixing time and get close result. Dimensionless global mixing time remains unchanged with increasing of impeller speed. Parallel, merging and diverging flow pattern form in the agitated tank, respectively, by changing the impeller spacing and clearance of lower impeller from the bottom of the tank. The global mixing time is the shortest for the merging flow, followed by diverging flow, and the longest for parallel flow. The research presents helpful references for design, optimization and scale-up of agitated tanks with multi-impeller.

Agitation in cognitive disorders: International Psychogeriatric Association provisional consensus clinical and research definition.

PubMed

Cummings, Jeffrey; Mintzer, Jacobo; Brodaty, Henry; Sano, Mary; Banerjee, Sube; Devanand, D P; Gauthier, Serge; Howard, Robert; Lanctôt, Krista; Lyketsos, Constantine G; Peskind, Elaine; Porsteinsson, Anton P; Reich, Edgardo; Sampaio, Cristina; Steffens, David; Wortmann, Marc; Zhong, Kate

2015-01-01

Agitation is common across neuropsychiatric disorders and contributes to disability, institutionalization, and diminished quality of life for patients and their caregivers. There is no consensus definition of agitation and no widespread agreement on what elements should be included in the syndrome. The International Psychogeriatric Association formed an Agitation Definition Work Group (ADWG) to develop a provisional consensus definition of agitation in patients with cognitive disorders that can be applied in epidemiologic, non-interventional clinical, pharmacologic, non-pharmacologic interventional, and neurobiological studies. A consensus definition will facilitate communication and cross-study comparison and may have regulatory applications in drug development programs. The ADWG developed a transparent process using a combination of electronic, face-to-face, and survey-based strategies to develop a consensus based on agreement of a majority of participants. Nine-hundred twenty-eight respondents participated in the different phases of the process. Agitation was defined broadly as: (1) occurring in patients with a cognitive impairment or dementia syndrome; (2) exhibiting behavior consistent with emotional distress; (3) manifesting excessive motor activity, verbal aggression, or physical aggression; and (4) evidencing behaviors that cause excess disability and are not solely attributable to another disorder (psychiatric, medical, or substance-related). A majority of the respondents rated all surveyed elements of the definition as "strongly agree" or "somewhat agree" (68-88% across elements). A majority of the respondents agreed that the definition is appropriate for clinical and research applications. A provisional consensus definition of agitation has been developed. This definition can be used to advance interventional and non-interventional research of agitation in patients with cognitive impairment.

A Longitudinal Examination of Agitation and Resident Characteristics in the Nursing Home

ERIC Educational Resources Information Center

Burgio, Louis D.; Park, Nan Sook; Hardin, J. Michael; Sun, Fei

2007-01-01

Purpose: Agitation frequently accompanies cognitive decline among nursing home residents. This study used cross-sectional and longitudinal (up to 18 months) methods to examine agitation among profoundly and moderately impaired residents using both staff report and direct observation methods. Design and Methods: The study included participants (N =…

40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2014 CFR

2014-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2011 CFR

2011-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2013 CFR

2013-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2012 CFR

2012-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

Code of Federal Regulations, 2010 CFR

2010-07-01

... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service; and...

Hypokalemia and agitation in acute psychotic patients.

PubMed

Hatta, K; Takahashi, T; Nakamura, H; Yamashiro, H; Asukai, N; Yonezawa, Y

1999-04-19

Hypokalemia is caused partly by intensive exercise. Some evidence suggests that psychological distress may cause hypokalemia. The relationship between the decline of serum potassium concentration and the level of symptoms of acute agitation, which was defined as a total score on a subset of six categories on the 18-item Brief Psychiatric Rating Scale (anxiety, tension, mannerism and posturing, hostility, uncooperativeness, psychomotor excitement), was examined in 313 schizophrenic men, admitted on an emergency basis during a 24-month period. In addition, change in serum potassium concentration after sedation was investigated. Serum potassium concentration in the severely agitated group was lower than that in the mild group. There was a significant correlation between serum potassium concentration and the level of symptoms of acute agitation (r = -0.30, P < 0.0001). Although the decline of serum potassium concentration in the patients who were sufficiently sedated improved within 8 h, that in the patients showing high scores on the acute agitation subset even 8 h after emergency admission was prolonged. Results indicate that sedation improves acute agitation-induced hypokalemia. rights

The minimum record time for PIV measurement in a vessel agitated by a Rushton turbine

NASA Astrophysics Data System (ADS)

Šulc, Radek; Ditl, Pavel; Fořt, Ivan; Jašíkova, Darina; Kotek, Michal; Kopecký, Václav; Kysela, Bohuš

In PIV studies published in the literature focusing on the investigation of the flow field in an agitated vessel the record time is ranging from the tenths and the units of seconds. The aim of this work was to determine minimum record time for PIV measurement in a vessel agitated by a Rushton turbine that is necessary to obtain relevant results of velocity field. The velocity fields were measured in a fully baffled cylindrical flat bottom vessel 400 mm in inner diameter agitated by a Rushton turbine 133 mm in diameter using 2-D Time Resolved Particle Image Velocimetry in the impeller Reynolds number range from 50 000 to 189 000. This Re range secures the fully-developed turbulent flow of agitated liquid. Three liquids of different viscosities were used as the agitated liquid. On the basis of the analysis of the radial and axial components of the mean- and fluctuation velocities measured outside the impeller region it was found that dimensionless minimum record time is independent of impeller Reynolds number and is equalled N.tRmin = 103 ± 19.

USSR and Eastern Europe Scientific Abstracts, Biomedical and Behavioral Sciences. Number 70

DTIC Science & Technology

1977-05-04

are quite dependent on type of plant. Figures 5; Table 1; References 4: 1 Russian, 3 Western. USSR UDC 626.843+631.54 AERATING TREATMENT OF THE SOD...perennial grasses, application of mineral fertilizers and the aeration treatment described above) lengthens the productive year of irrigated...pastures, producing a harvest of 6-8*103 feed units/ha. Aerating treatment of the soddy layer is thus a promising method of cultivation of pastures

A combined system of microbial fuel cell and intermittently aerated biological filter for energy self-sufficient wastewater treatment.

PubMed

Dong, Yue; Feng, Yujie; Qu, Youpeng; Du, Yue; Zhou, Xiangtong; Liu, Jia

2015-12-15

Energy self-sufficiency is a highly desirable goal of sustainable wastewater treatment. Herein, a combined system of a microbial fuel cell and an intermittently aerated biological filter (MFC-IABF) was designed and operated in an energy self-sufficient manner. The system was fed with synthetic wastewater (COD = 1000 mg L(-1)) in continuous mode for more than 3 months at room temperature (~25 °C). Voltage output was increased to 5 ± 0.4 V using a capacitor-based circuit. The MFC produced electricity to power the pumping and aeration systems in IABF, concomitantly removing COD. The IABF operating under an intermittent aeration mode (aeration rate 1000 ± 80 mL h(-1)) removed the residual nutrients and improved the water quality at HRT = 7.2 h. This two-stage combined system obtained 93.9% SCOD removal and 91.7% TCOD removal (effluent SCOD = 61 mg L(-1), TCOD = 82.8 mg L(-1)). Energy analysis indicated that the MFC unit produced sufficient energy (0.27 kWh m(-3)) to support the pumping system (0.014 kWh m(-3)) and aeration system (0.22 kWh m(-3)). These results demonstrated that the combined MFC-IABF system could be operated in an energy self-sufficient manner, resulting to high-quality effluent.

Internal aeration of paddy field rice (Oryza sativa) during complete submergence---importance of light and floodwater O2.

PubMed

Winkel, Anders; Colmer, Timothy D; Ismail, Abdelbagi M; Pedersen, Ole

2013-03-01

Flash floods can submerge paddy field rice (Oryza sativa), with adverse effects on internal aeration, sugar status and survival. Here, we investigated the in situ aeration of roots of rice during complete submergence, and elucidated how underwater photosynthesis and floodwater pO(2) influence root aeration in anoxic soil. In the field, root pO(2) was measured using microelectrodes during 2 d of complete submergence. Leaf gas films that formed on the superhydrophobic leaves were left intact, or experimentally removed, to elucidate their effect on internal aeration. In darkness, root pO(2) declined to very low concentrations (0.24 kPa) and was strongly correlated with floodwater pO(2). In light, root pO(2) was high (14 kPa) and primarily a function of the incident light determining the rates of underwater net photosynthesis. Plants with intact leaf gas films maintained higher underwater net photosynthesis relative to plants without gas films when the submerged shoots were in light. During complete submergence, internal aeration of rice in the field relies on underwater photosynthesis during the day and entry of O(2) from the floodwater during the night. Leaf gas films enhance photosynthesis during submergence leading to improved O(2) production and sugar status, and therefore contribute to the submergence tolerance of rice. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Modelling oxygen transfer using dynamic alpha factors.

PubMed

Jiang, Lu-Man; Garrido-Baserba, Manel; Nolasco, Daniel; Al-Omari, Ahmed; DeClippeleir, Haydee; Murthy, Sudhir; Rosso, Diego

2017-11-01

Due to the importance of wastewater aeration in meeting treatment requirements and due to its elevated energy intensity, it is important to describe the real nature of an aeration system to improve design and specification, performance prediction, energy consumption, and process sustainability. Because organic loadings drive aeration efficiency to its lowest value when the oxygen demand (energy) is the highest, the implications of considering their dynamic nature on energy costs are of utmost importance. A dynamic model aimed at identifying conservation opportunities is presented. The model developed describes the correlation between the COD concentration and the α factor in activated sludge. Using the proposed model, the aeration efficiency is calculated as a function of the organic loading (i.e. COD). This results in predictions of oxygen transfer values that are more realistic than the traditional method of assuming constant α values. The model was applied to two water resource recovery facilities, and was calibrated and validated with time-sensitive databases. Our improved aeration model structure increases the quality of prediction of field data through the recognition of the dynamic nature of the alpha factor (α) as a function of the applied oxygen demand. For the cases presented herein, the model prediction of airflow improved by 20-35% when dynamic α is used. The proposed model offers a quantitative tool for the prediction of energy demand and for minimizing aeration design uncertainty. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel open-type biosensor for the in-situ monitoring of biochemical oxygen demand in an aerobic environment

PubMed Central

Yamashita, Takahiro; Ookawa, Natsuki; Ishida, Mitsuyoshi; Kanamori, Hiroyuki; Sasaki, Harumi; Katayose, Yuichi; Yokoyama, Hiroshi

2016-01-01

Biochemical oxygen demand (BOD) is a widely used index of water-quality assessment. Since bioelectrochemical BOD biosensors require anaerobic conditions for anodic reactions, they are not directly used in aerobic environments such as aeration tanks. Normally, the BOD biosensors are closed-type, where the anode is packed inside a closed chamber to avoid exposure to oxygen. In this study, a novel bioelectrochemical open-type biosensor was designed for in-situ monitoring of BOD during intermittent aeration. The open-type anode, without any protection against exposure to oxygen, was directly inserted into an intermittently aerated tank filled with livestock wastewater. Anodic potential was controlled using a potentiostat. Interestingly, this novel biosensor generated similar levels of current under both aerating and non-aerating conditions, and showed a logarithmic correlation (R2 > 0.9) of current with BOD concentrations up to 250 mg/L. Suspended solids in the wastewater attached to and covered the whole anode, presumably leading to the production of anaerobic conditions inside the covered anode via biological oxygen removal. Exoelectrogenic anaerobes (Geobacter spp.) were detected inside the covered anode using the 16S-rRNA gene. This biosensor will have various practical applications, such as the automatic control of aeration intensity and the in-situ monitoring of natural water environments. PMID:27917947

Aerated drilling cutting transport analysis in geothermal well

NASA Astrophysics Data System (ADS)

Wakhyudin, Aris; Setiawan, Deni; Dwi Marjuan, Oscar

2017-12-01

Aeratad drilling widely used for geothermal drilling especially when drilled into predicted production zone. Aerated drilling give better performance on preventing lost circulation problem, improving rate of penetration, and avoiding drilling fluid invasion to productive zone. While well is drilled, cutting is produced and should be carried to surface by drilling fluid. Hole problem, especially pipe sticking will occur while the cutting is not lifted properly to surface. The problem will effect on drilling schedule; non-productive time finally result more cost to be spent. Geothermal formation has different characteristic comparing oil and gas formation. Geothermal mainly has igneous rock while oil and gas mostly sedimentary rock. In same depth, formation pressure in geothermal well commonly lower than oil and gas well while formation temperature geothermal well is higher. While aerated drilling is applied in geothermal well, Igneous rock density has higher density than sedimentary rock and aerated drilling fluid is lighter than water based mud hence minimum velocity requirement to transport cutting is larger than in oil/gas well drilling. Temperature and pressure also has impact on drilling fluid (aerated) density. High temperature in geothermal well decrease drilling fluid density hence the effect of pressure and temperature also considered. In this paper, Aerated drilling cutting transport performance on geothermal well will be analysed due to different rock and drilling fluid density. Additionally, temperature and pressure effect on drilling fluid density also presented to merge.

Influence of forced air volume on water evaporation during sewage sludge bio-drying.

PubMed

Cai, Lu; Chen, Tong-Bin; Gao, Ding; Zheng, Guo-Di; Liu, Hong-Tao; Pan, Tian-Hao

2013-09-01

Mechanical aeration is critical to sewage sludge bio-drying, and the actual water loss caused by aeration can be better understood from investigations of the relationship between aeration and water evaporation from the sewage sludge bio-drying pile based on in situ measurements. This study was conducted to investigate the effects of forced air volume on the evaporation of water from a sewage sludge bio-drying pile. Dewatered sewage sludge was bio-dried using control technology for bio-drying, during which time the temperature, superficial air velocity and water evaporation were measured and calculated. The results indicated that the peak air velocity and water evaporation occurred in the thermophilic phase and second temperature-increasing phase, with the highest values of 0.063 ± 0.027 m s(-1) and 28.9 kg ton(-1) matrix d(-1), respectively, being observed on day 4. Air velocity above the pile during aeration was 43-100% higher than when there was no aeration, and there was a significantly positive correlation between air volume and water evaporation from day 1 to 15. The order of daily means of water evaporation was thermophilic phase > second temperature-increasing phase > temperature-increasing phase > cooling phase. Forced aeration controlled the pile temperature and improved evaporation, making it the key factor influencing water loss during the process of sewage sludge bio-drying. Copyright © 2013 Elsevier Ltd. All rights reserved.

Impact of fouling on the decline of aeration efficiency under different operational conditions at WRRFs.

PubMed

Garrido-Baserba, Manel; Asvapathanagul, Pitiporn; Park, Hee-Deung; Kim, Taek-Seung; Baquero-Rodriguez, G Andres; Olson, Betty H; Rosso, Diego

2018-10-15

Biofilm formation influences the most energy-demanding process in the waste water treatment cycle. Biofilm growth on the surface of wastewater aeration diffusers in water resource recovery facilities (WRRFs) can increase the energy requirements up to 50% in less than 2 years. The impact of biofilms in aeration diffusers was quantified and assessed for first time using molecular tools (i.e., Energy-dispersive X-ray, Ra and RMS and Pyrosequencing) and state-of-the-art techniques (i.e., EPS quantification, Hydrophobicity and DNA quantification). To provide a better understanding and quantitative connections between biological activity and aeration energy efficiency, two replicates of the most common diffusers were installed and tested in two different operational conditions (higher and lower organic loading rate processes) during 15 months. Different scenarios and conditions provided for first time comprehensive understanding of the major factors contributing to diffuser fouling. The array of analysis suggested that higher loading conditions can promote specialized microbial populations to halve aeration efficiency parameters (i.e., αF) in comparison to lower loading conditions. Biofilms adapted to certain operational conditions can trigger changes in diffuser membrane properties (i.e., biological enhanced roughness and hydrophobicity) and enhance EPS growth rates. Improved understanding of the effects of scaling, biofouling, aging and microbial population shifts on the decrease in aeration efficiency is provided. Copyright © 2018 Elsevier B.V. All rights reserved.

Municipal waste stabilization in a reactor with an integrated active and passive aeration system.

PubMed

Kasinski, Slawomir; Slota, Monika; Markowski, Michal; Kaminska, Anna

2016-04-01

To test whether an integrated passive and active aeration system could be an effective solution for aerobic decomposition of municipal waste in technical conditions, a full-scale composting reactor was designed. The waste was actively aerated for 5d, passively aerated for 35 d, and then actively aerated for 5d, and the entire composting process was monitored. During the 45-day observation period, changes in the fractional, morphological and physico-chemical characteristics of the waste at the top of the reactor differed from those in the center of the reactor. The fractional and morphological analysis made during the entire process of stabilization, showed the total reduction of organic matter measured of 82 wt% and 86 wt% at the respective depths. The reduction of organic matter calculated using the results of Lost of Ignition (LOI) and Total Organic Carbon (TOC) showed, respectively, 40.51-46.62% organic matter loss at the top and 45.33-53.39% in the center of the reactor. At the end of the process, moisture content, LOI and TOC at the top were 3.29%, 6.10% and 4.13% higher, respectively, than in the center. The results showed that application of passive aeration in larger scale simultaneously allows the thermophilic levels to be maintained during municipal solid waste composting process while not inhibiting microbial activity in the reactor. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recirculation or artificial aeration in vertical flow constructed wetlands: a comparative study for treating high load wastewater.

PubMed

Foladori, Paola; Ruaben, Jenny; Ortigara, Angela R C

2013-12-01

Vertical subsurface-flow constructed wetlands at pilot-scale have been applied to treat high hydraulic and organic loads by implementing the following configurations: (1) intermittent recirculation of the treated wastewater from the bottom to the top of the bed, (2) intermittent artificial aeration supplied at the bottom of the bed and (3) the combination of both. These configurations were operated with a saturated bottom layer for a 6h-treatment phase, followed by a free drainage phase prior to a new feeding. COD removal efficiency was 85-90% in all the configurations and removed loads were 54-70 gCOD m(-2)d(-1). The aerated and recirculated wetland resulted in a higher total nitrogen removal (8.6 gN m(-2)d(-1)) due to simultaneous nitrification/denitrification, even in the presence of intermittent aeration (6.8 Nm(3)m(-2)d(-1)). The extra investment needed for implementing aeration/recirculation would be compensated for by a reduction of the surface area per population equivalent, which decreased to 1.5m(2)/PE. Copyright © 2013 Elsevier Ltd. All rights reserved.

Composite wastewater treatment by aerated electrocoagulation and modified peroxi-coagulation processes.

PubMed

Kumar, Abhijeet; Nidheesh, P V; Suresh Kumar, M

2018-08-01

Treatment of composite wastewater generating from the industrial estates is a great challenge. The present study examines the applicability of aerated electrocoagulation and modified peroxi-coagulation processes for removing color and COD from composite wastewater. Iron plates were used as anodes and cathodes in both electrochemical processes and experiments were carried out in a working volume of 2 L. Aeration enhanced the efficiency of electrocoagulation process significantly. More than 50% of COD and 60% of color were removed after 1 h of electrocoagulation process operated at pH 3 and applied voltage of 1 V. Efficiency of the modified peroxi-coagulation process was significantly higher than that of aerated electrocoagulation. COD and color removal efficiencies of the modified peroxi-coagulation process were found as 77.7% and 97%, respectively after 1 h of electrolysis operated at 1 V, solution pH 3 and 50 mM hydrogen peroxide addition. This improved efficiency of modified peroxi-coagulation compared to aerated electrocoagulation is mainly due to the attack of in-situ generated hydroxyl radicals. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of micro-aeration on anaerobic digestion of primary sludge under septic tank conditions.

PubMed

Diak, James; Örmeci, Banu; Kennedy, Kevin J

2013-04-01

Micro-aeration, which refers to the addition of very small amounts of air, is a simple technology that can potentially be incorporated in septic tanks to improve the digestion performance. The purpose of this study was to investigate and compare the effects of micro-aeration on anaerobic digestion of primary sludge under septic tank conditions. 1.6 L batch reactor experiments were carried out in duplicate using raw primary sludge, with 4.1 % total solids, and diluted primary sludge, with 2.1 % total solids. Reactors were operated for 5 weeks at room temperature to simulate septic tank conditions. Micro-aeration rate of 0.00156 vvm effectively solubilised chemical oxygen demand (COD) and improved the subsequent degradation of COD. Micro-aeration also increased the generation of ammonia and soluble proteins, but did not improve the reduction in total and volatile solids, or the reduction in carbohydrates. Experiments using diluted sludge samples showed similar trends as the experiments with raw sludge, which suggest that initial solids concentration did not have a significant effect on the degradation of primary sludge under septic tank conditions.

In-patient costs of agitation and containment in a mental health catchment area.

PubMed

Serrano-Blanco, Antoni; Rubio-Valera, Maria; Aznar-Lou, Ignacio; Baladón Higuera, Luisa; Gibert, Karina; Gracia Canales, Alfredo; Kaskens, Lisette; Ortiz, José Miguel; Salvador-Carulla, Luis

2017-06-06

There is a scarce number of studies on the cost of agitation and containment interventions and their results are still inconclusive. We aimed to calculate the economic consequences of agitation events in an in-patient psychiatric facility providing care for an urban catchment area. A mixed approach combining secondary analysis of clinical databases, surveys and expert knowledge was used to model the 2013 direct costs of agitation and containment events for adult inpatients with mental disorders in an area of 640,572 adult inhabitants in South Barcelona (Spain). To calculate costs, a seven-step methodology with novel definition of agitation was used along with a staff survey, a database of containment events, and data on aggressive incidents. A micro-costing analysis of specific containment interventions was used to estimate both prevalence and direct costs from the healthcare provider perspective, by means of a mixed approach with a probabilistic model evaluated on real data. Due to the complex interaction of the multivariate covariances, a sensitivity analysis was conducted to have empirical bounds of variability. During 2013, 918 patients were admitted to the Acute Inpatient Unit. Of these, 52.8% were men, with a mean age of 44.6 years (SD = 15.5), 74.4% were compulsory admissions, 40.1% were diagnosed with schizophrenia or non-affective psychosis, with a mean length of stay of 24.6 days (SD = 16.9). The annual estimate of total agitation events was 508. The cost of containment interventions ranges from 282€ at the lowest level of agitation to 822€ when verbal containment plus seclusion and restraint have to be used. The annual total cost of agitation was 280,535€, representing 6.87% of the total costs of acute hospitalisation in the local area. Agitation events are frequent and costly. Strategies to reduce their number and severity should be implemented to reduce costs to the Health System and alleviate patient suffering.

Effect of nature-based sound therapy on agitation and anxiety in coronary artery bypass graft patients during the weaning of mechanical ventilation: A randomised clinical trial.

PubMed

Aghaie, Bahman; Rejeh, Nahid; Heravi-Karimooi, Majideh; Ebadi, Abbas; Moradian, Seyed Tayeb; Vaismoradi, Mojtaba; Jasper, Melanie

2014-04-01

Weaning from mechanical ventilation is a frequent nursing activity in critical care. Nature-based sound as a non-pharmacological and nursing intervention effective in other contexts may be an efficient approach to alleviating anxiety, agitation and adverse effects of sedative medication in patients undergoing weaning from mechanical ventilation. This study identified the effect of nature-based sound therapy on agitation and anxiety on coronary artery bypass graft patients during weaning from mechanical ventilation. A randomised clinical trial design was used. 120 coronary artery bypass graft patients aged 45-65 years undergoing weaning from mechanical ventilation were randomly assigned to intervention and control groups. Patients in the intervention group listened to nature-based sounds through headphones; the control group had headphones with no sound. Haemodynamic variables, anxiety levels and agitation were assessed using the Faces Anxiety Scale and Richmond Agitation Sedation Scale, respectively. Patients in both groups had vital signs recorded after the first trigger, at 20 min intervals throughout the procedure, immediately after the procedure, 20 min after extubation, and 30 min after extubation. Data were collected over 5 months from December 2012 to April 2013. The intervention group had significantly lower anxiety and agitation levels than the control group. Regarding haemodynamic variables, a significant time trend and interaction was reported between time and group (p<0.001). A significant difference was also found between the anxiety (p<0.002) and agitation (p<0.001) scores in two groups. Nature-based sound can provide an effective method of decreasing potential adverse haemodynamic responses arising from anxiety and agitation in weaning from mechanical ventilation in coronary artery bypass graft patients. Nurses can incorporate this intervention as a non-pharmacological intervention into the daily care of patients undergoing weaning from mechanical ventilation in order to reduce their anxiety and agitation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Patient preferences for medicine administration for acute agitation: results from an internet-based survey of patients diagnosed with bipolar disorder or schizophrenia in two Nordic countries.

PubMed

Jørgensen, Tine Rikke; Emborg, Charlotte; Dahlen, Karianne; Bøgelund, Mette; Carlborg, Andreas

2018-01-01

The objective was to elicit patient preferences for medicine administration method in the management of acute agitation episodes among patients diagnosed with bipolar disorder or schizophrenia. The patients' experiences of acute agitation episodes and their management of episodes were also explored. Data were collected via an anonymous, internet-based survey of residents in Denmark or Sweden with schizophrenia or bipolar disorder (October 2014 to December 2014). Inclusion criteria were having a diagnosis of schizophrenia or bipolar disorder, and being above 18 years of age. The questionnaire included questions about preferences for medication attributes, experiences with pharmacological treatment for agitation and involvement in treatment plans. A total of 237 diagnosed patients (61 with schizophrenia; 176 with bipolar disorder) completed the questionnaire. Agitation episodes were experienced by 90% of the respondents. In total, 83% of the respondents reported having received treatment with tablets. When patients were presented with the attributes of an inhalation method, respondents stated that the fast onset of action, low risk of adverse reactions and least invasive form of drug delivery were positive attributes of treatment with inhalation. Inhalation is a new delivery route for treatment of acute agitation in patients diagnosed with bipolar disorder or schizophrenia. Inhalation is the preferred treatment method for acute agitation among Danish and Swedish patients with bipolar disorder or schizophrenia.

Valproate for agitation in critically ill patients: A retrospective study.

PubMed

Gagnon, David J; Fontaine, Gabriel V; Smith, Kathryn E; Riker, Richard R; Miller, Russell R; Lerwick, Patricia A; Lucas, F L; Dziodzio, John T; Sihler, Kristen C; Fraser, Gilles L

2017-02-01

The purpose was to describe the use of valproate therapy for agitation in critically ill patients, examine its safety, and describe its relationship with agitation and delirium. This retrospective cohort study evaluated critically ill adults treated with valproate for agitation from December 2012 through February 2015. Information on valproate prescribing practices and safety was collected. Incidence of agitation, delirium, and concomitant psychoactive medication use was compared between valproate day 1 and valproate day 3. Concomitant psychoactive medication use was analyzed using mixed models. Fifty-three patients were evaluated. The median day of valproate therapy initiation was ICU day 7, and it was continued for a median of 7 days. The median maintenance dose was 1500 mg/d (23 mg/kg/d). The incidence of agitation (96% vs 61%, P < .0001) and delirium (68% vs 49%, P = .012) significantly decreased by valproate day 3. Treatment with opioids (77% vs 65%, P = .02) and dexmedetomidine (47% vs 24%, P = .004) also decreased. In mixed models analyses, valproate therapy was associated with reduced fentanyl equivalents (-185 μg/d, P = .0003) and lorazepam equivalents (-2.1 mg/d, P = .0004). Hyperammonemia (19%) and thrombocytopenia (13%) were the most commonly observed adverse effects. Valproate therapy was associated with a reduction in agitation, delirium, and concomitant psychoactive medication use within 48 hours of initiation. Copyright © 2016 Elsevier Inc. All rights reserved.

Prevalence and risk factors of agitation in newly hospitalized schizophrenia patients in China: An observational survey.

PubMed

Mi, Weifeng; Zhang, Suzhen; Liu, Qi; Yang, Fude; Wang, Yong; Li, Tao; Mei, Qiyi; He, Hongbo; Chen, Zhiyu; Su, Zhonghua; Liu, Tiebang; Xie, Shiping; Tan, Qingrong; Zhang, Jinbei; Zhang, Congpei; Sang, Hong; Chen, Wenhao; Shi, Le; Li, Lingzhi; Shi, Ying; Guo, Lihua; Zhang, Hongyan; Lu, Lin

2017-07-01

This multi-center observational study investigated the prevalence of agitation in newly hospitalized schizophrenia patients in China and its potential risk factors. It was performed in 2014 and covered 14 hospitals. Newly hospitalized patients with schizophrenia or suspected schizophrenia who met the diagnostic criteria of the International Statistical Classification of Diseases and Related Health Problems, 10th revision, were recruited. Agitation and related risk factors were evaluated by a questionnaire designed for the survey. General demographic data, disease characteristics, scores on schizophrenia rating scales and agitation rating scales (e.g., Positive and Negative Syndrome Scale-Excited Component [PANSS-EC] and Behavioral Activity Rating Scale [BARS]) were collected. Among the 1512 patients screened in the study, 1400 (92.59%) were eligible. According to the PANSS-EC and BARS, the prevalence of agitation was 60.92% (853 of 1400) and 59.00% (826 of 1400), respectively. The overall prevalence of agitation was 47.50% (665 of 1400). The most important risk factor of agitation was being aggressive at baseline (Modified Overt Aggression Scale score ≥4, odds ratio=6.54; 95% confidence interval=4.93-8.69). Other risk factors included a history of aggressive behavior, northern region of residence, involuntary hospitalization, disease severity, low level of education, living alone, being unemployed or retired. Copyright © 2017. Published by Elsevier B.V.

Behavioral Characteristics of Agitated Nursing Home Residents with Dementia at the End of Life

ERIC Educational Resources Information Center

Allen, Rebecca S.; Burgio, Louis D.; Fisher, Susan E.; Hardin, J. Michael; Shuster, John L., Jr.

2005-01-01

Purpose: The purpose of this study was to examine group differences in verbal agitation, verbal interaction, bed restraint, pain, analgesic and neuroleptic medication use, and medical comorbidity among agitated nursing home residents who died during a 6-month clinical trial compared with residents of the same gender and similar initial cognitive…

The Relationship between Agitated Behavior and Cognitive Functioning in Nursing Home Residents: Preliminary Results.

ERIC Educational Resources Information Center

Cohen-Mansfield, Jiska

Agitation is a significant problem for nursing home residents, their families, and their caretakers. Agitation is defined as inappropriate verbal, vocal, or motor activity which is not explained by needs or confusion per se. It includes behaviors such as aimless wandering, pacing, cursing, screaming, biting, and fighting. The inappropriate nature…

40 CFR 63.173 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Equipment Leaks § 63.173 Standards: Agitators in gas/vapor service and in light liquid service. (a)(1) Each... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 63.173 Section 63.173 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1028 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Standards § 63.1028 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1028 Section 63.1028 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1028 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Standards § 63.1028 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1028 Section 63.1028 Protection of Environment ENVIRONMENTAL...

40 CFR 63.173 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Equipment Leaks § 63.173 Standards: Agitators in gas/vapor service and in light liquid service. (a)(1) Each... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 63.173 Section 63.173 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1028 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Standards § 63.1028 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1028 Section 63.1028 Protection of Environment ENVIRONMENTAL...

40 CFR 65.109 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Standards: Agitators in gas/vapor service and in light liquid service. (a) Compliance schedule. The owner or... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 65.109 Section 65.109 Protection of Environment ENVIRONMENTAL...

40 CFR 63.173 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Equipment Leaks § 63.173 Standards: Agitators in gas/vapor service and in light liquid service. (a)(1) Each... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 63.173 Section 63.173 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1009 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... § 63.1009 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1009 Section 63.1009 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1009 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... § 63.1009 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1009 Section 63.1009 Protection of Environment ENVIRONMENTAL...

40 CFR 65.109 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Standards: Agitators in gas/vapor service and in light liquid service. (a) Compliance schedule. The owner or... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 65.109 Section 65.109 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1028 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Standards § 63.1028 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1028 Section 63.1028 Protection of Environment ENVIRONMENTAL...

40 CFR 65.109 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Standards: Agitators in gas/vapor service and in light liquid service. (a) Compliance schedule. The owner or... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 65.109 Section 65.109 Protection of Environment ENVIRONMENTAL...

40 CFR 63.173 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Equipment Leaks § 63.173 Standards: Agitators in gas/vapor service and in light liquid service. (a)(1) Each... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 63.173 Section 63.173 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1009 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 63.1009 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1009 Section 63.1009 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1009 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... § 63.1009 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1009 Section 63.1009 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1028 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Standards § 63.1028 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1028 Section 63.1028 Protection of Environment ENVIRONMENTAL...

40 CFR 65.109 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Standards: Agitators in gas/vapor service and in light liquid service. (a) Compliance schedule. The owner or... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 65.109 Section 65.109 Protection of Environment ENVIRONMENTAL...

40 CFR 63.1009 - Agitators in gas and vapor service and in light liquid service standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... § 63.1009 Agitators in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Agitators in gas and vapor service and in light liquid service standards. 63.1009 Section 63.1009 Protection of Environment ENVIRONMENTAL...

40 CFR 63.173 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Equipment Leaks § 63.173 Standards: Agitators in gas/vapor service and in light liquid service. (a)(1) Each... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 63.173 Section 63.173 Protection of Environment ENVIRONMENTAL...

40 CFR 65.109 - Standards: Agitators in gas/vapor service and in light liquid service.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Standards: Agitators in gas/vapor service and in light liquid service. (a) Compliance schedule. The owner or... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Standards: Agitators in gas/vapor service and in light liquid service. 65.109 Section 65.109 Protection of Environment ENVIRONMENTAL...

Acid mine water aeration and treatment system

DOEpatents

Ackman, Terry E.; Place, John M.

1987-01-01

An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

The Effects of White Noise on Agitated Behaviors, Mental Status, and Activities of Daily Living in Older Adults With Dementia.

PubMed

Lin, Li-Wei; Weng, Shu-Chuan; Wu, Hua-Shan; Tsai, Lu-Jen; Lin, Ya-Ling; Yeh, Shu-Hui

2018-02-01

The aging of society is a global trend, and care of older adults with dementia is an urgent challenge. As dementia progresses, patients exhibit negative emotions, memory disorders, sleep disorders, and agitated behavior. Agitated behavior is one of the most difficult problems for family caregivers and healthcare providers to handle when caring for older adults with dementia. The aim of this study was to investigate the effectiveness of white noise in improving agitated behavior, mental status, and activities of daily living in older adults with dementia. An experimental research design was used to study elderly participants two times (pretest and posttest). Six dementia care centers in central and southern Taiwan were targeted to recruit participants. There were 63 participants: 28 were in the experimental group, and 35 were in the comparison group. Experimental group participants received 20 minutes of white noise consisting of ocean, rain, wind, and running water sounds between 4 and 5 P.M. daily over a period of 4 weeks. The comparison group received routine care. Questionnaires were completed, and observations of agitated behaviors were collected before and after the intervention. Agitated behavior in the experimental group improved significantly between pretest and posttest. Furthermore, posttest scores on the Mini-Mental Status Examination and Barthel Index were slightly better for this group than at pretest. However, the experimental group registered no significant difference in mental status or activities of daily living at posttest. For the comparison group, agitated behavior was unchanged between pretest and posttest. The results of this study support white noise as a simple, convenient, and noninvasive intervention that improves agitated behavior in older adults with dementia. These results may provide a reference for related healthcare providers, educators, and administrators who care for older adults with dementia.

Synergistic effect of microbubble emulsion and sonic or ultrasonic agitation on endodontic biofilm in vitro.

PubMed

Halford, Andrew; Ohl, Claus-Dieter; Azarpazhooh, Amir; Basrani, Bettina; Friedman, Shimon; Kishen, Anil

2012-11-01

Irrigation dynamics and antibacterial activity determine the efficacy of root canal disinfection. Sonic or ultrasonic agitation of irrigants is expected to improve irrigation dynamics. This study examined the effects of microbubble emulsion (ME) combined with sonic or ultrasonic agitation on irrigation dynamics and reduction of biofilm bacteria within root canal models. Two experiments were conducted. First, high-speed imaging was used to characterize the bubble dynamics generated in ME by sonic or ultrasonic agitation within canals of polymer tooth models. Second, 5.25% NaOCl irrigation or ME was sonically or ultrasonically agitated in canals of extracted teeth with 7-day-grown Enterococcus faecalis biofilms. Dentinal shavings from canal walls were sampled at 1 mm and 3 mm from the apical terminus, and colony-forming units (CFUs) were enumerated. Mean log CFU/mL values were analyzed with analysis of variance and post hoc tests. High-speed imaging demonstrated strongly oscillating and vaporizing bubbles generated within ME during ultrasonic but not sonic agitation. Compared with CFU counts in controls, NaOCl-sonic and NaOCl-ultrasonic yielded significantly lower counts (P < .05) at both measurement levels. ME-sonic yielded significantly lower counts (P = .002) at 3 mm, whereas ME-ultrasonic yielded highly significantly lower counts (P = .000) at both measurement levels. At 3 mm, ME-ultrasonic yielded significantly lower CFU counts (P = .000) than ME-sonic, NaOCl-sonic, and NaOCl-ultrasonic. Enhanced bubble dynamics and reduced E. faecalis biofilm bacteria beyond the level achieved by sonic or ultrasonic agitation of NaOCl suggested a synergistic effect of ME combined with ultrasonic agitation. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Addressing Dual Patient and Staff Safety Through A Team-Based Standardized Patient Simulation for Agitation Management in the Emergency Department.

PubMed

Wong, Ambrose H; Auerbach, Marc A; Ruppel, Halley; Crispino, Lauren J; Rosenberg, Alana; Iennaco, Joanne D; Vaca, Federico E

2018-06-01

Emergency departments (EDs) have seen harm rise for both patients and health workers from an increasing rate of agitation events. Team effectiveness during care of this population is particularly challenging because fear of physical harm leads to competing interests. Simulation is frequently employed to improve teamwork in medical resuscitations but has not yet been reported to address team-based behavioral emergency care. As part of a larger investigation of agitated patient care, we designed this secondary study to examine the impact of an interprofessional standardized patient simulation for ED agitation management. We used a mixed-methods approach with emergency medicine resident and attending physicians, Physician Assistants (PAs) and Advanced Practice Registered Nurses (APRNs), ED nurses, technicians, and security officers at two hospital sites. After a simulated agitated patient encounter, we conducted uniprofessional and interprofessional focus groups. We undertook structured thematic analysis using a grounded theory approach. Quantitative data consisted of responses to the KidSIM Questionnaire addressing teamwork and simulation-based learning attitudes before and after each session. We reached data saturation with 57 participants. KidSIM scores revealed significant improvements in attitudes toward relevance of simulation, opportunities for interprofessional education, and situation awareness, as well as four of six questions for roles/responsibilities. Two broad themes emerged from the focus groups: (1) a team-based agitated patient simulation addressed dual safety of staff and patients simultaneously and (2) the experience fostered interprofessional discovery and cooperation in agitation management. A team-based simulated agitated patient encounter highlighted the need to consider the dual safety of staff and patients while facilitating interprofessional dialog and learning. Our findings suggest that simulation may be effective to enhance teamwork in behavioral emergency care.

Effects of Agitation and Storage Temperature on Measurements of Hydration Status.

PubMed

Adams, Heather M; Eberman, Lindsey E; Yeargin, Susan W; Niemann, Andrew J; Mata, Heather L; Dziedzicki, David J

2015-12-01

Hypohydration can have significant implications on normal physiological functions of the body. This study aimed to determine the impact of agitation, storage temperature, and storage time on urine osmolality compared to the criterion control. We used a descriptive diagnostic validity test design. To investigate agitation, we recruited 75 healthy individuals (males = 41, females = 34; mean age = 22 ± 5 years; mean self-reported height = 172 ± 23 cm and mass = 77 ± 17 kg) who provided one or more samples (total = 81). The independent variables were agitation (vortex, hand shaken, no agitation) and temperature (room temperature, freezer, and refrigerator) type. Participants completed informed consent, a health questionnaire and were asked to provide a urine sample, which was split and labeled according to agitation type or storage temperature. Urine osmolality was used to determine hydration status at two time points (within 2 hours [control], 48 hours). We used t-tests to determine the difference between each condition and the control and calculated percent error for each condition. No significant differences for no agitation (t79 = -0.079, P = 0.937), hand shaken (t79 = 1.395, P = 0.167) or vortex mixed (t79 = -0.753, P = 0.453) were identified when compared to the criterion control. No significant differences for room temperature (t82 = -0.720, P = 0.474), refrigerator (t82 = -2.697, P = 0.008) or freezer (t82 = 2.576, P = 0.012) were identified when compared to the criterion control. Our findings suggest agitation of urine specimen is not necessary and samples do not require refrigeration or freezing if assessed within 48 hours. Analysis within two hours of collection is not necessary and samples can be stored for up to 48 hours without impacting the hydration status of the sample.

An investigation of the interactive effects of the capability for suicide and acute agitation on suicidality in a military sample.

PubMed

Ribeiro, Jessica D; Bender, Theodore W; Buchman, Jennifer M; Nock, Matthew K; Rudd, M David; Bryan, Craig J; Lim, Ingrid C; Baker, Monty T; Knight, Chadwick; Gutierrez, Peter M; Joiner, Thomas E

2015-01-01

According to the interpersonal theory of suicide (1, 2), the difficulties inherently associated with death by suicide deter many individuals from engaging in suicidal behavior. Consistent with the notion that suicide is fearsome, acute states of heightened arousal are commonly observed in individuals immediately prior to lethal and near-lethal suicidal behavior. We suggest that among individuals who possess elevated levels of the capability for suicide, the heightened state of arousal experienced during periods of acute agitation may facilitate suicidal behavior in part because it would provide the necessary energy to approach a potentially lethal stimulus. Among individuals who are low on capability, the arousal experienced during agitation may result in further avoidance. In the present project we examine how acute agitation may interact with the capability for suicide to predict suicidality in a large military sample (n = 1,208) using hierarchical multiple regression. Results were in line with a priori hypotheses: among individuals high on capability, as agitation increases, suicidality increases whereas as agitation increases among individuals low on capability, suicidality decreases. Results held beyond the effects of thwarted belongingness, perceived burdensomeness, and suicidal cognitions. Beyond further substantiating the link between agitation and suicide, findings of the present study provide evidence for the construct validity of the acquired capability as well as offer initial evidence for moderating role of capability on the effect of agitation on suicide. Limitations of the current study highlight a need for future research that improves upon the techniques used in the present study. Implications for science and practice are discussed. © 2014 Wiley Periodicals, Inc.

Porosimetric, Thermal and Strength Tests of Aerated and Nonaerated Concretes

NASA Astrophysics Data System (ADS)

Strzałkowski, Jarosław; Garbalińska, Halina

2017-10-01

The paper presents the results of porosimetry tests of lightweight concretes, obtained with three research methods. Impact of different porosity structures on the basic thermal and strength properties was also evaluated. Tests were performed, using the pressure gauge method on fresh concrete mixes, as well as using the mercury porosimetry test and optic RapidAir method on specimens prepared from mature composites. The study was conducted on lightweight concretes, based on expanded clay aggregate and fly ash aggregate, in two variants: with non-aerated and aerated cement matrix. In addition, two reference concretes, based on normal aggregate, were prepared, also in two variants of matrix aeration. Changes in thermal conductivity λ and volumetric specific heat cv throughout the first three months of curing of the concretes were examined. Additionally, tests for compressive strength on cubic samples were performed during the first three months of curing. It was found that the pressure gauge method, performed on a fresh mix, gave lowered values of porosity, compared to the other methods. The mercury porosity tests showed high sensitivity in evaluation of pores smaller than 30μm. Unfortunately, this technique is not suitable for analysing pores greater than 300μm. On the other hand, the optical method proves good in evaluation of large pores, greater than 300μm. The paper also presents results of correlation of individual methods of porosity testing. A consolidated graph of the pore structure, derived from both mercury and optical methods, was presented, too. For the all of six tested concretes, differential graphs of porosity, prepared with both methods, show a very broad convergence. The thermal test results indicate usefulness of aeration of the cement matrix of the composites based on lightweight aggregates for the further reduction of the thermal conductivity coefficient λ of the materials. The lowest values of the λ coefficient were obtained for the aerated concretes based of fly ash aggregate. A diminishing influence of aeration on the volumetric heat capacity cv is clearly seen. Simultaneous aeration of the matrix and use of lightweight aggregates brought about also a significant decrease in the average compressive strength fcm of the tested composites.

Culture characteristics of the atmospheric and room temperature plasma-mutated Spirulina platensis mutants in CO2 aeration culture system for biomass production.

PubMed

Tan, Yinyee; Fang, Mingyue; Jin, Lihua; Zhang, Chong; Li, He-Ping; Xing, Xin-Hui

2015-10-01

For biomass production of Spirulina platensis as feedstock of fermentation, the culture characteristics of three typical mutants of 3-A10, 3-B2 and 4-B3 generated by atmospheric and room temperature plasmas (ARTP) mutagenesis were systematically studied by using CO2 aeration culture system and compared with the wild strain. The specific growth rate of wild strain in the pure air aeration culture system exhibited a 76.2% increase compared with static culture, while the specific growth rates of the 3-A10, 3-B2 and 4-B3 in pure air aeration culture system were increased by 114.4%, 95.9% and 88.2% compared with their static cultures. Compared with static culture, the carbohydrate contents of wild strain, 3-A10, 3-B2 and 4-B3 in pure air aeration culture system dropped plainly by 51.0%, 79.3%, 85.5% and 26.1%. Increase of CO2 concentration enhanced carbohydrate content and productivity. Based on the carbohydrate productivity, the optimal inlet of CO2 concentration in aeration culture was determined to be 12% (v/v). Under this condition, 3-B2 exhibited the highest carbohydrate content (30.7%), CO2 fixation rate (0.120gCO2·g(-1)·d(-1)) and higher growth rate (0.093 g L(-1)·d(-1)), while 3-A10 showed the highest growth rate (0.118 g L(-1)·d(-1)) and higher CO2 fixation rate (0.117gCO2·g(-1)·d(-1)) but low carbohydrate content (24.5%), and 4-B3 showed the highest chlorophyll (Chl) content (3.82 mg·g(-1)). The most outstanding mutant by static culture in terms of growth rate and carbohydrate productivity (3-B2), was also demonstrated by CO2 aeration culture system. This study revealed that the ARTP mutagenesis could generate the S. platensis mutants suitable for CO2 aeration culture aiming at biomass production. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Soil Aeration deficiencies in urban sites

NASA Astrophysics Data System (ADS)

Weltecke, Katharina; Gaertig, Thorsten

2010-05-01

Soil aeration deficiencies in urban sites Katharina Weltecke and Thorsten Gaertig On urban tree sites reduction of soil aeration by compaction or sealing is an important but frequently underestimated factor for tree growth. Up to 50% of the CO2 assimilated during the vegetation period is respired in the root space (Qi et al. 1994). An adequate supply of the soil with oxygen and a proper disposal of the exhaled carbon dioxide are essential for an undisturbed root respiration. If the soil surface is smeared, compacted or sealed, soil aeration is interrupted. Several references show that root activity and fine root growth are controlled by the carbon dioxide concentration in soil air (Qi et al.1994, Burton et al. 1997). Gaertig (2001) found that decreasing topsoil gas permeability leads to reduced fine root density and hence to injury in crown structure of oaks. In forest soils a critical CO2 concentration of more than 0.6 % indicates a bad aeration status (Gaertig 2001). The majority of urban tree sites are compacted or sealed. The reduction of soil aeration may lead to dysfunctions in the root space and consequently to stress during periods of drought, which has its visible affects in crown structure. It is reasonable to assume that disturbances in soil aeration lead to reduced tree vigour and roadworthiness, resulting in high maintenance costs. The assessment of soil aeration in urban sites is difficult. In natural ecosystems the measurement of gas diffusivity and the gas-chromatical analysis of CO2 in soil air are accepted procedures in analyzing the state of aeration (Schack-Kirchner et al. 2001, Gaertig 2001). It has been found that these methods can also be applied for analyzing urban sites. In particular CO2 concentration in the soil atmosphere can be considered as a rapidly assessable, relevant and integrating indicator of the aeration situation of urban soils. This study tested the working hypothesis that soil aeration deficiencies lead to a decrease of fine root density and tree vigour on urban soils. For that purpose gas diffusivity, soil CO2 concentrations and fine root density were measured on typical urban sites in the German cities of Göttingen, Mannheim, and Kassel. The known characteristics of soil aeration on forest sites could be affirmed for urban soils. A negative correlation was found between gas diffusion coefficients and CO2 concentration as well as between fine root extension and CO2 concentration. Changes in crown structure of beech indicating a loss of vigour were found at sites with disturbed aeration. Diffusivity patterns and CO2 concentrations of different specific urban soil sealing types were found. On more natural sites (mulch, grass) increased gas diffusion and low CO2 concentration were present. In contrast, on more compacted or sealed areas (asphalt, paving stone, macadamised road surface) the exchange between soil air and atmosphere was nearly disconnected and soil CO2 concentrations partly exceeded the known critical value of 0.6 % up to tenfold. Literature Burton, A. J.; Pregitzer, K. S.; Zogg, G. P. und Zak D. R. (1997): Effect of measurement CO2 concentrations on sugar maple root respiration. In: Canadian journal of Forest Research, H. 17, S. 421-427. Gaertig, T. (2001): Bodengashaushalt, Feinwurzeln und Vitalität von Eichen. In: Freiburger Bodenkundliche Abhandlungen, H. 40, S. 157. Qi, J.; Marshall, J. D.; Mattson, K. G. (1994): High soil carbon dioxide concentrations inhibit root respiration of Douglas fir. In: New Phytol., Jg. 128, H. 3, S. 435-442. Schack-Kirchner, H.; Gaertig, T.; Wilpert, K. v.; Hildebrand, E. E. (2001): A modified McIntyre and Phillip approach to measure top-soil gas diffusivity in-situ. In: J. Plant Nutr. Soil Sci., Jg. 164, S. 253-258.

Role of citalopram in the treatment of agitation in Alzheimer’s disease

PubMed Central

Porsteinsson, Anton P; Keltz, Melanie A; Smith, Jessica S

2014-01-01

SUMMARY Neuropsychiatric symptoms (NPS) are common among individuals with Alzheimer’s disease (AD), associated with excess morbidity and mortality, greater healthcare use, earlier institutionalization, and caregiver burden. Agitation presents as emotional distress, excessive psychomotor activity, aggressive behaviors, disruptive irritability and dishibition. There is an unmet need to find pharmacologic treatment for agitation in patients with AD that can be safely and effectively used as a concurrent treatment alongside psychosocial interventions. A recent, multicenter, randomized, placebo-controlled trial explored the efficacy of a 30-mg daily dose of citalopram for agitation in patients with AD and showed a significant decrease in agitation for citalopram compared with placebo. Both QTc prolongation and cognitive worsening, as measured by the Mini Mental State Examination, were observed in the citalopram group and present a concern to clinicians. Citalopram at a 20-mg daily dose should be considered as a possible first-line treatment in addition to psychosocial intervention. PMID:25405648

Discontinuing the Use of PRN Intramuscular Medication for Agitation in an Acute Psychiatric Hospital.

PubMed

Hayes, Ariel; Russ, Mark J

2016-03-01

This study examined the impact of eliminating intramuscular PRN medication for agitation on patient and staff safety in an acute psychiatric inpatient setting. The current retrospective chart review investigated the use of PRN medications (oral and intramuscular) to treat acute agitation, including aggression, and related outcomes before and after a mandated change in PRN practice that required real time physician input before administration of intramuscular medications. The use of both oral and intramuscular PRN medications dramatically decreased following implementation of the mandated change in practice. In particular, the use of intramuscular PRNs for agitation decreased by about half. Despite this decrease, the assault rate in the hospital was unchanged, and the utilization of restraint and seclusion continued to decrease. It is possible to reduce the utilization of PRN medications for agitation without broadly compromising safety on acute care psychiatric inpatient units.

Correlates Among Nocturnal Agitation, Sleep, and Urinary Incontinence in Dementia

PubMed Central

Rose, Karen; Specht, Janet; Forch, Windy

2016-01-01

Family caregivers of elders with dementia often face the challenging behaviors of nighttime agitation, sleep disturbances, and urinary incontinence. To date, no study has examined the interrelationships of these behaviors in community-dwelling persons. This single group, descriptive study employs wireless body sensors to objectively collect data on nighttime agitation, sleep, and urinary incontinence in patients with dementia in their homes over a 5- to 7-day period. The aims are to (1) examine the feasibility and acceptability of the use of body sensors in community-dwelling persons with dementia; (2) describe patterns of nocturnal agitation, sleep continuity and duration, and nighttime urinary incontinence; and (3) examine the relationships among nocturnal agitation, sleep continuity and duration, and nighttime urinary incontinence. Data collection is in early stages and is still in progress. Challenges and advantages from preliminary data collection are reported. PMID:24670931

This is Not a History Lesson; This is Agitation: A Call for a Methodology of Diffraction in US-Based Community Psychology.

PubMed

Langhout, Regina Day

2016-12-01

Agitation, as deployed by the Industrial Areas Foundation (IAF), occurs when imaginations and curiosities are piqued, and self-interest is made visible. In this framework, agitation is a step in creating change. In this paper, I outline two agitations within US-based community psychology. I then describe a third agitation that is underway; I add my voice and call for a methodology of diffraction as a contribution to critical reflexivity practices within US-based community psychology. Consistent with the IAF framework, I do not provide solutions. I write this paper as a provocation to help us think imaginatively and creatively about our actions and future, so that we can consider the paradigm shifts needed to move into critical ways of understanding connection, responsibility, accountability, and creating change-of interest during Swampscott and today. © Society for Community Research and Action 2016.

Simple and Reproducible Two-Stage Agitation Speed Control Strategy for Enhanced Triterpene Production by Lingzhi or Reishi Medicinal Mushrooms, Ganoderma lucidum ACCC G0119 (Higher Basidiomycetes) Based on Submerged Liquid Fermentation.

PubMed

Feng, Jie; Feng, Na; Yang, Yan; Liu, Fang; Zhang, Jingsong; Jia, Wei; Lin, Chi-Chung

2015-01-01

Triterpenes are important anticancer agents produced by batch submerged liquid fermentation, with the medicinal mushroom Ganoderma lucidum ACCC G0119, which was investigated under various dissolved oxygen levels by varying agitation speeds. Three kinetic parameters were analyzed: specific mycelial growth rate (μsmg), specific glucose consumption rate (qsgc), and specific triterpene production rate (qstp). High concentration, yield, and productivity of triterpenes were achieved by developing a simple and reproducible two-stage agitation speed control strategy. At the first 40 h, agitation speed was controlled at 150 rpm to obtain the quickest peak qstp for triterpene production, subsequently agitation speed was controlled at 100 rpm to maintain high qstp for high triterpene accumulation. The maximum concentration of triterpenes reached 0.086 g/l with the yield of 6.072 g/kg and the productivity of 6.532 × 10-4 g/(l·h), which were 39.61%, 36.48%, and 49.22%, respectively, better than the best results controlled by fixed agitation speeds. Conceivably, such a triterpene fermentation production strategy would be useful for industrial large-scale production of triterpenes with G. lucidum.

Dementia-related agitation: a review of non-pharmacological interventions and analysis of risks and benefits of pharmacotherapy

PubMed Central

Ijaopo, E O

2017-01-01

Unsurprisingly, the subject of dementia has been a rising matter of public health concerns as people now live longer. World Alzheimer Report 2015, estimate that about 46.8 million people worldwide have dementia. These numbers are projected to almost double every 20 years, reaching 74.7 million in 2030 and 131.5 million in 2050. The modality for treating agitation and other behavioral symptoms in dementia patients has been a challenge. Many years on, there has been no FDA-approved pharmacotherapy in treating dementia-related agitation. This review discusses the current knowledge of non-pharmacological interventions, and analyzes the risks and benefits of pharmacotherapy in the management of dementia-related agitation, as well as providing an anecdotal of the author's clinical experience. This article aims to provide opportunity for increase awareness for clinicians, particularly those with no specialty training in geriatrics medicine but see dementia patients with agitation and other behavioral symptoms from time to time. Likewise, it hopefully will benefit the readers of medical journals to update their existing knowledge on matters relating to the management of dementia-related agitation. PMID:29087372

Advancements in the treatment of agitation in Alzheimer's disease.

PubMed

Antonsdottir, Inga M; Smith, Jessica; Keltz, Melanie; Porsteinsson, Anton P

2015-01-01

Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) are associated with significant negative outcomes for patients and their caregivers. Agitation, one of the most distressing NPS, lacks well-established long-term interventions that are both effective and safe. While non-pharmacological interventions are the suggested first-line treatment, it isn't effective in managing symptoms for every patient. In such cases, clinicians turn to the use of pharmacological interventions. Traditionally, these interventions consist of off-label use of antipsychotics, sedative/hypnotics, anxiolytics, acetylcholinesterase inhibitors, memantine and antidepressants, where the efficacy doesn't necessarily outweigh the associated risks. Gains made in understanding the neurobiological mechanisms underlying agitation have fueled several recent clinical trials. A comprehensive literature search for published articles evaluating pharmacologic interventions for agitation in AD was done. A review of some of these clinical trials was completed: dextromethorphan/quinidine, scyllo-inositol, brexpiprazole, prazosin, cannabinoids, dronabinol and citalopram show promise in treating agitation. Neurobiological findings and enhanced trial designs have re-ignited the area of pharmacological treatment of NPS. Although further research is needed to fully determine the safety, tolerability and efficacy of these treatments, the mission to finding effective treatments for NPS such as agitation in patients with dementia is well underway.

Behavioral interventions for agitation in older adults with dementia: an evaluative review.

PubMed

Spira, Adam P; Edelstein, Barry A

2006-06-01

Older adults with dementia commonly exhibit agitated behavior that puts them at risk of injury and institutionalization and is associated with caregiver stress. A range of theoretical approaches has produced numerous interventions to manage these behavior problems. This paper critically reviews the empirical literature on behavioral interventions to reduce agitation in older adults with dementia. A literature search yielded 23 articles that met inclusion criteria. These articles described interventions that targeted wandering, disruptive vocalization, physical aggression, other agitated behaviors and a combination of these behaviors. Studies are summarized individually and then evaluated. Behavioral interventions targeting agitated behavior exhibited by older adults with dementia show considerable promise. A number of methodological issues must be addressed to advance this research area. Problem areas include inconsistent use of functional assessment techniques, failure to report quantitative findings and inadequate demonstrations of experimental control. The reviewed studies collectively provide evidence that warrants optimism regarding the application of behavioral principles to the management of agitation among older adults with dementia. Although the results of some studies were mixed and several studies revealed methodological shortcomings, many of them offered innovations that can be used in future, more rigorously designed, intervention studies.

Anxiety or agitation in mood disorder with mixed features: A review with a focus on validity as a dimensional criterion.

PubMed

Shim, In Hee; Bae, Dong Sik; Bahk, Won-Myong

2016-08-01

The diagnostic validity of mixed features, excluding anxiety or psychomotor agitation in mood disorders, has not yet been fully examined. PubMed and relevant English-language literature (regardless of year) were searched. Keywords were mixed or mixed state or mixed features or mixed episode and anxious or anxiety or agitation and bipolar disorder or depressive disorder or mood disorder or affective disorder. Most studies on anxiety or psychomotor agitation have included a significant correlation relevant to the "with mixed features" specifier, although it is common in both poles of mood episodes regardless of the predominant polarity. There is some confusion between the characteristic of classical mixed states and the definition of the mixed features specifier with the newly added anxious distress specifier in DSM-5, specifically, whether to include anxiety and agitation as significant characteristics. This change is of concern because a large proportion of patients with mixed features are now unspecified, and this may influence treatment planning and prognosis. The findings of our review suggest that anxiety and psychomotor agitation can be core symptoms in mood episodes with mixed features and important clinical clues for prediction of treatment effects and disease course.

A combined system of microbial fuel cell and intermittently aerated biological filter for energy self-sufficient wastewater treatment

PubMed Central

Dong, Yue; Feng, Yujie; Qu, Youpeng; Du, Yue; Zhou, Xiangtong; Liu, Jia

2015-01-01

Energy self-sufficiency is a highly desirable goal of sustainable wastewater treatment. Herein, a combined system of a microbial fuel cell and an intermittently aerated biological filter (MFC-IABF) was designed and operated in an energy self-sufficient manner. The system was fed with synthetic wastewater (COD = 1000 mg L−1) in continuous mode for more than 3 months at room temperature (~25 °C). Voltage output was increased to 5 ± 0.4 V using a capacitor-based circuit. The MFC produced electricity to power the pumping and aeration systems in IABF, concomitantly removing COD. The IABF operating under an intermittent aeration mode (aeration rate 1000 ± 80 mL h−1) removed the residual nutrients and improved the water quality at HRT = 7.2 h. This two-stage combined system obtained 93.9% SCOD removal and 91.7% TCOD removal (effluent SCOD = 61 mg L−1, TCOD = 82.8 mg L−1). Energy analysis indicated that the MFC unit produced sufficient energy (0.27 kWh m−3) to support the pumping system (0.014 kWh m−3) and aeration system (0.22 kWh m−3). These results demonstrated that the combined MFC-IABF system could be operated in an energy self-sufficient manner, resulting to high-quality effluent. PMID:26666392

Effect of synthetic iron colloids on the microbiological NH(4)(+) removal process during groundwater purification.

PubMed

Wolthoorn, Anke; Temminghoff, Erwin J M; van Riemsdijk, Willem H

2004-04-01

Subsurface aeration is used to oxidise Fe in situ in groundwater that is used to make drinking water potable. In a groundwater system with pH>7 subsurface aeration results in non-mobile Fe precipitate and mobile Fe colloids. Since originally the goal of subsurface aeration is to remove iron in situ, the formation of non-mobile iron precipitate, which facilitates the metal's removal, is the desired result. In addition to this intended effect, subsurface aeration may also strongly enhance the microbiological removal of ammonium (NH(4)(+)) in the purification station. Mobile iron colloids could be the link between subsurface aeration and the positive effect on the NH(4)(+) removal process. Therefore, the objective of this study was to assess whether synthetic iron colloids could improve the NH(4)(+) removal process. The effect of synthetic iron colloids on the NH(4)(+) removal process was studied using an artificial purification set-up on a laboratory scale. Columns that purified groundwater with or without added synthetic iron colloids were set up in duplicate. The results showed that the NH(4)(+) removal was significantly ( alpha = 0.05 ) increased in columns treated with the synthetic iron colloids. Cumulative after 4 months about 10% more NH(4)(+) was nitrified in the columns that was treated with the groundwater containing synthetic iron colloids. The results support the hypothesis that mobile iron colloids could be the link between subsurface aeration and the positive effect on the NH(4)(+) removal process.

Performance of intermittent aeration reactor on NH4-N removal from groundwater resources.

PubMed

Khanitchaidecha, W; Nakamura, T; Sumino, T; Kazama, F

2010-01-01

To study the effect of intermittent aeration period on ammonium-nitrogen (NH4-N) removal from groundwater resources, synthetic groundwater was prepared and three reactors were operated under different conditions--"reactor A" under continuous aeration, "reactor B" under 6 h intermittent aeration, and "reactor C" under 2 h intermittent aeration. To facilitate denitrification simultaneously with nitrification, "acetate" was added as an external carbon source with step-wise increase from 0.5 to 1.5 C/N ratio, where C stands for total carbon content in the system, and N for NH4-N concentration in the synthetic groundwater. Results show that complete NH4-N removal was obtained in "reactor B" and "reactor C" at 1.3 and 1.5 C/N ratio respectively; and partial NH4-N removal in "reactor A". These results suggest that intermittent aeration at longer interval could enhance the reactor performance on NH4-N removal in terms of efficiency and low external carbon requirement. Because of consumption of internal carbon by the process, less amount of external carbon is required. Further increase in carbon in a form of acetate (1.5 to 2.5 C/N ratios) increases removal rate (represented by reaction rate coefficient (k) of kinetic equation) as well as occurrence of free cells. It suggests that the operating condition at reactor B with 1.3 C/N ratio is more appropriate for long-term operation at a pilot-scale.

Effectiveness of Inhaled Loxapine in Dual-Diagnosis Patients: A Case Series.

PubMed

Roncero, Carlos; Ros-Cucurull, Elena; Grau-López, Lara; Fadeuilhe, Christian; Casas, Miguel

2016-01-01

Episodes of psychotic agitation are frequent in patients with dual diagnosis, that is, in patients with concomitant psychiatric and substance use disorders. Rapid intervention is needed to treat the agitation at a mild stage to prevent the escalation to aggressive behavior. Inhaled loxapine has been demonstrated to rapidly improve symptoms of mild-to-moderate agitation in adults with psychiatric disorders (schizophrenia and bipolar disorder), but data on patients with dual diagnosis are scarce. This study is a retrospective review of data from a case series of patients with dual diagnosis, which were attended for symptoms of agitation while at the emergency room (n = 9), in the outpatient clinic (n = 4), or during hospitalization (n = 1) at 1 center in Spain. All patients received inhaled loxapine for treating the agitation episodes. Data from 14 patients with dual diagnosis were reviewed. All patients had 1 or more psychiatric disorders (schizophrenia, bipolar I disorder, drug-induced psychotic disorder, posttraumatic stress, borderline or antisocial personality disorder, depression, or anxiety) along with a variety of substance use disorders (alcohol, cocaine, cannabis, amphetamines, hypnotics and antianxiety drugs, caffeine, or street drugs). Overall, only 1 dose of inhaled loxapine (9.1 mg) was needed to calm each patient during an acute episode of agitation. Inhaled loxapine was rapid, effective, and well accepted in all dual-pathology patients presenting with acute agitation in the emergency setting. Inhaled loxapine facilitated both patient cooperation and an adequate management of his or her disease.

Enhancing nitrogen removal in an Orbal oxidation ditch by optimization of oxygen supply: practice in a full-scale municipal wastewater treatment plant.

PubMed

Zhou, Xin; Guo, Xuesong; Han, Yunping; Liu, Junxin; Ren, Jincheng; Wang, Yu; Guo, Yantao

2012-09-01

Seven different aeration modes, in which oxygen supply was changed by adjusting the number of aerators, were designed and applied in a full-scale municipal wastewater treatment plant with Orbal oxidation ditch to investigate the influence of dissolved oxygen (DO) on nitrogen removal performance. The full-scale experiment results of 574 days showed that nitrogen removal efficiency depended on the degree of nitrification and denitrification in the outer channel, which was the largest contributor for TN removal in the Orbal oxidation ditch. Appropriate aeration control in the outer channel was essential to balance nitrification and denitrification in the Orbal oxidation ditch. When DO was as low as about 0.2 mg/L in the outer channel, the highest TN removal efficiency of 75% was obtained. Microbial analysis confirmed that aerobic and anaerobic bacteria coexisted in the outer channel. The greater species diversity and more intensive activities of these bacteria in aeration Mode V may be responsible for the higher TN removal efficiency compared with Mode III. These results suggest that different aerated conditions in the Orbal oxidation ditch might have a significant effect on microbial community characteristics and nitrogen removal efficiencies.

Feasibility study of a V-shaped pipe for passive aeration composting.

PubMed

Ogunwande, Gbolabo A

2011-03-01

A V-shaped (Vs) pipe was improvised for composting of chicken litter in passive aeration piles. Three piles, equipped with horizontal (Ho), vertical (Ve) and Vs pipes were set up. The three treatments were replicated thrice. The effects of the aeration pipe on the physico-chemical properties of chicken litter and air distribution within the composting piles were investigated during composting. The properties monitored were temperature, pH, electrical conductivity, moisture content, total carbon, total nitrogen, total phosphorus and carbon-to-nitrogen ratio. Moisture level in the piles was replenished fortnightly to 60% during composting. The results of the study showed that all the piles attained the optimum temperature range (40-65°C) for effective composting and satisfied the requirements for sanitation. The non-significant (p > 0.05) temperature difference within the piles with Ve and Vs pipes indicated that these pipes were effective for uniform air distribution within the pile. The aeration pipe had significant (p ≤ 0.05) effect on pile temperature, pre-replenishment moisture content, pH and total phosphorus. In conclusion, the study showed that the Vs pipe is feasible and effective for passive aeration composting.

Effects of subsurface aeration and trinexapac-ethyl application on soil microbial communities in a creeping bentgrass putting green

USGS Publications Warehouse

Feng, Y.; Stoeckel, D.M.; Van Santen, E.; Walker, R.H.

2002-01-01

The sensitivity of creeping bentgrass (Agrostis palustris Huds.) to the extreme heat found in the southeastern United States has led to the development of new greens-management methods. The purpose of this study was to examine the effects of subsurface aeration and growth regulator applications on soil microbial communities and mycorrhizal colonization rates in a creeping bentgrass putting green. Two cultivars (Crenshaw and Penncross), a growth regulator (trinexapacethyl), and subsurface aeration were evaluated in cool and warm seasons. Total bacterial counts were higher in whole (unsieved) soils than in sieved soils, indicating a richer rhizosphere soil environment. Mycorrhizal infection rates were higher in trinexapac-ethyl (TE) treated plants. High levels of hyphal colonization and relatively low arbuscule and vesicle occurrence were observed. Principal components analysis of whole-soil fatty acid methyl ester (FAME) profiles indicated that warm-season microbial populations in whole and sieved soils had similar constituents, but the populations differed in the cool season. FAME profiles did not indicate that subsurface aeration and TE application affected soil microbial community structure. This is the first reported study investigating the influences of subsurface aeration and TE application on soil microorganisms in a turfgrass putting green soil.

Treatment of landfill leachate using an aerated, horizontal subsurface-flow constructed wetland.

PubMed

Nivala, J; Hoos, M B; Cross, C; Wallace, S; Parkin, G

2007-07-15

A pilot-scale subsurface-flow constructed wetland was installed at the Jones County Municipal Landfill, near Anamosa, Iowa, in August 1999 to demonstrate the use of constructed wetlands as a viable low-cost treatment option for leachate generated at small landfills. The system was equipped with a patented wetland aeration process to aid in removal of organic matter and ammonia nitrogen. The high iron content of the leachate caused the aeration system to cease 2 years into operation. Upon the installation of a pretreatment chamber for iron removal and a new aeration system, treatment efficiencies dramatically improved. Seasonal performance with and without aeration is reported for 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), ammonia nitrogen (NH(4)-N), and nitrate nitrogen (NO(3)-N). Since winter air temperatures in Iowa can be very cold, a layer of mulch insulation was installed on top of the wetland bed to keep the system from freezing. When the insulation layer was properly maintained (either through sufficient litterfall or replenishing the mulch layer), the wetland sustained air temperatures of as low as -26 degrees C without freezing problems.

Renewable energy for the aeration of wastewater ponds.

PubMed

Hobus, I; Hegemann, W

2003-01-01

The application of a decentralised renewable energy supply for the aeration of wastewater ponds, and the influence of an unsteady oxygen supply on the specific conversion rate and biocoenose was investigated. With the discontinuous aeration the specific conversion rate is increased as compared to facultative ponds. The estimation of the microorganisms consortia was done with in situ hybridisation techniques. A significant shift in the bacteria population with the chosen specific probes for anaerobic, sulphate reducing and nitrifying bacteria could not be detected. Wastewater ponds have sufficient buffer volume to compensate for the fluctuating energy supply. But the efficiency of the energy supply of a photovoltaic plant decreases in shallow lakes (d < 1.5 m) corresponding to a high oxygen production of algae. For the layout of the individual components: photovoltaic and wind power plant, energy management, aeration system and wastewater pond, a simulation model was developed and tested. The application of renewable energy for the aeration of wastewater ponds is a useful alternative for the redevelopment of overloaded ponds as well as the construction of new wastewater ponds, especially in areas with an inadequate central electricity grid and a high availability of wind and solar energy.

Effect of long-term successive storm flows on water reclamation plant resilience.

PubMed

Zhu, Jun-Jie; Anderson, Paul R

2017-03-15

A water reclamation plant (WRP) needs to be resilient to successfully operate through different kinds of perturbations. Perturbations such as storm events, especially long-term successive storm flows, can adversely affect operations. A better understanding of these effects can provide benefits for plant operation, in terms of effluent quality and energy efficiency. However, the concept of resilience for a WRP has not been widely studied, and we are not aware of any studies specifically related to storm flows. In this work we applied measures of resistance and recovery time to quantify resilience, and used a WRP simulation model to investigate how different storm flow characteristics (flowrate and duration) and the amount of aeration influence resilience. Not surprisingly, increasing storm flowrate leads to decreasing resilience. Although the aeration rate plays an important role in determining resilience, there is an aeration threshold (6 m 3 /s for our WRP model); higher aeration rates do not increase resilience. Results suggest that aeration costs could be reduced by as much as 50% while still maintaining the resilience needed to meet effluent quality permit requirements through the perturbations examined in this study. Copyright © 2016 Elsevier Ltd. All rights reserved.

A GUIDE TO AERATION/CIRCULATION TECHNIQUES FOR ...

EPA Pesticide Factsheets

The application of aeration/circulation techniques to lakes are reviewed from a theoretical and practical viewpoint. The effect of destratification on algal production is related to the mixed depth with the use of a mathematical model. Procedures are given to determine air required to mix lakes of different sizes and shapes. It was found that approximately 30 scfm of air per 1,000,000 sq ft of lake surface area can be used. Hypolimnetic aeration systems that have been used are described in detail. Procedures for design are given.

Turbulence and wave breaking effects on air-water gas exchange

PubMed

Boettcher; Fineberg; Lathrop

2000-08-28

We present an experimental characterization of the effects of turbulence and breaking gravity waves on air-water gas exchange in standing waves. We identify two regimes that govern aeration rates: turbulent transport when no wave breaking occurs and bubble dominated transport when wave breaking occurs. In both regimes, we correlate the qualitative changes in the aeration rate with corresponding changes in the wave dynamics. In the latter regime, the strongly enhanced aeration rate is correlated with measured acoustic emissions, indicating that bubble creation and dynamics dominate air-water exchange.

Experimental study of defoaming by air-borne power ultrasonic technology

NASA Astrophysics Data System (ADS)

Rodríguez, Germán; Riera, Enrique; Gallego-Juárez, Juan A.; Acosta, Víctor M.; Pinto, Alberto; Martínez, Ignacio; Blanco, Alfonso

2010-01-01

Foam is a dispersion of gas in a liquid in which the distances between the gas bubbles are very small. Foams are frequently generated in the manufacture of many products as result from the aeration and agitation of liquids, from the vaporization of the liquid and also from biological or chemical reactions. Foams are generally an unwanted product in industrial processes because they cause difficulties in process control and in equipment operation. The most efficient conventional method for defoaming is the use of chemical agents but they contaminate the product. High-intensity ultrasonic waves offer a clean procedure to break foam bubbles. The potential use of ultrasound for foam breaking that was known since many years has been recently reinforced by the application of a new type of ultrasonic defoamer based on the stepped-plate high-power transducers to generate air-borne ultrasound. This defoamer has been successfully applied in several industrial problems such as the control of excess foam produced during the filling operation of bottles and cans on high-speed canning lines and in fermenting vessels and other reactors of great dimensions. The treatment of such industrial problems requires the proper characterization and quantification of the main parameters involved in the mechanisms of the defoaming effect. This paper deals with an experimental study about the separate influence of such parameters with the aim of improving the application of the stepped-plate power ultrasonic generators for the production of the defoaming action on industrial processes

Enhancement of Oxygen Mass Transfer and Gas Holdup Using Palm Oil in Stirred Tank Bioreactors with Xanthan Solutions as Simulated Viscous Fermentation Broths

PubMed Central

Mohd Sauid, Suhaila; Huey Ling, Tan; Veluri, Murthy V. P. S.

2013-01-01

Volumetric mass transfer coefficient (k L a) is an important parameter in bioreactors handling viscous fermentations such as xanthan gum production, as it affects the reactor performance and productivity. Published literatures showed that adding an organic phase such as hydrocarbons or vegetable oil could increase the k L a. The present study opted for palm oil as the organic phase as it is plentiful in Malaysia. Experiments were carried out to study the effect of viscosity, gas holdup, and k L a on the xanthan solution with different palm oil fractions by varying the agitation rate and aeration rate in a 5 L bench-top bioreactor fitted with twin Rushton turbines. Results showed that 10% (v/v) of palm oil raised the k L a of xanthan solution by 1.5 to 3 folds with the highest k L a value of 84.44 h−1. It was also found that palm oil increased the gas holdup and viscosity of the xanthan solution. The k L a values obtained as a function of power input, superficial gas velocity, and palm oil fraction were validated by two different empirical equations. Similarly, the gas holdup obtained as a function of power input and superficial gas velocity was validated by another empirical equation. All correlations were found to fit well with higher determination coefficients. PMID:24350269

Evaluation of Gas Phase Dispersion in Flotation under Predetermined Hydrodynamic Conditions

NASA Astrophysics Data System (ADS)

Młynarczykowska, Anna; Oleksik, Konrad; Tupek-Murowany, Klaudia

2018-03-01

Results of various investigations shows the relationship between the flotation parameters and gas distribution in a flotation cell. The size of gas bubbles is a random variable with a specific distribution. The analysis of this distribution is useful to make mathematical description of the flotation process. The flotation process depends on many variable factors. These are mainly occurrences like collision of single particle with gas bubble, adhesion of particle to the surface of bubble and detachment process. These factors are characterized by randomness. Because of that it is only possible to talk about the probability of occurence of one of these events which directly affects the speed of the process, thus a constant speed of flotation process. Probability of the bubble-particle collision in the flotation chamber with mechanical pulp agitation depends on the surface tension of the solution, air consumption, degree of pul aeration, energy dissipation and average feed particle size. Appropriate identification and description of the parameters of the dispersion of gas bubbles helps to complete the analysis of the flotation process in a specific physicochemical conditions and hydrodynamic for any raw material. The article presents the results of measurements and analysis of the gas phase dispersion by the size distribution of air bubbles in a flotation chamber under fixed hydrodynamic conditions. The tests were carried out in the Laboratory of Instrumental Methods in Department of Environmental Engineering and Mineral Processing, Faculty of Mining and Geoengineerin, AGH Univeristy of Science and Technology in Krakow.

Strategies for improving production performance of probiotic Pediococcus acidilactici viable cell by overcoming lactic acid inhibition.

PubMed

Othman, Majdiah; Ariff, Arbakariya B; Wasoh, Helmi; Kapri, Mohd Rizal; Halim, Murni

2017-11-27

Lactic acid bacteria are industrially important microorganisms recognized for fermentative ability mostly in their probiotic benefits as well as lactic acid production for various applications. Fermentation conditions such as concentration of initial glucose in the culture, concentration of lactic acid accumulated in the culture, types of pH control strategy, types of aeration mode and different agitation speed had influenced the cultivation performance of batch fermentation of Pediococcus acidilactici. The maximum viable cell concentration obtained in constant fed-batch fermentation at a feeding rate of 0.015 L/h was 6.1 times higher with 1.6 times reduction in lactic acid accumulation compared to batch fermentation. Anion exchange resin, IRA 67 was found to have the highest selectivity towards lactic acid compared to other components studied. Fed-batch fermentation of P. acidilactici coupled with lactic acid removal system using IRA 67 resin showed 55.5 and 9.1 times of improvement in maximum viable cell concentration compared to fermentation without resin for batch and fed-batch mode respectively. The improvement of the P. acidilactici growth in the constant fed-batch fermentation indicated the use of minimal and simple process control equipment is an effective approach for reducing by-product inhibition. Further improvement in the cultivation performance of P. acidilactici in fed-bath fermentation with in situ addition of anion-exchange resin significantly helped to enhance the growth of P. acidilactici by reducing the inhibitory effect of lactic acid and thus increasing probiotic production.

Effect of medium components and culture conditions in Bacillus subtilis EA-CB0575 spore production.

PubMed

Posada-Uribe, Luisa F; Romero-Tabarez, Magally; Villegas-Escobar, Valeska

2015-10-01

Bacillus subtilis spores have important biotechnological applications; however, achieving both, high spore cell densities and sporulation efficiencies in fermentation, is poorly reported. In this study, medium components and culture conditions were optimized with different statistical methods to increase spore production of the plant growth promoting rhizobacteria B. subtilis EA-CB0575. Key medium components were determined with Plackett-Burman (PB) design, and the optimum concentration levels of two components (glucose, MgSO4·7H2O) were optimized with a full factorial and central composite design, achieving 1.37 × 10(9) CFU/mL of spore cell density and 93.5 % of sporulation efficiency in shake flask. The optimized medium was used to determine the effect of culture conditions on spore production at bioreactor level, finding that maintaining pH control did not affect significantly spore production, while the interaction of agitation and aeration rates had a significant effect on spore cell density. The overall optimization generated a 17.2-fold increase in spore cell density (8.78 × 10(9) CFU/mL) and 1.9-fold increase in sporulation efficiency (94.2 %) compared to that of PB design. These results indicate the potential of B. subtilis EA-CB0575 to produce both, high spore cell densities and sporulation efficiencies, with very low nutrient requirements and short incubation period which can represent savings of process production.

Utilization of Agro-Industry Residue for Rhamnolipid Production by P. aeruginosa AMB AS7 and Its Application in Chromium Removal.

PubMed

Samykannu, Mariaamalraj; Achary, Anant

2017-09-01

Coconut oil sludge and oil cake was utilized as carbon source for biosurfactant production by Pseudomonas aeruginosa AMB AS7. The results of optimization study revealed that 1.5% (w/v) of coconut oil cake, 2% (w/v) of coconut oil sludge, pH 7.2, 37 °C, and 120 rpm were the optimum conditions for biosurfactant production. The yield coefficient of biosurfactant on biomass (Y P/X ) was 1.29 g/g. Besides, the results indicated that aeration of 0.5 vvm and agitation of 450 rpm in bioreactor resulted in high volumetric productivity of biosurfactant (r p ) and specific product formation rate (q p ) of 0.115 g/(L h) and 0.0131 g/(g h), respectively in medium containing 2% (w/v) coconut oil sludge. The maximum biosurfactant concentration of 5.53 g/L was obtained during 60 h of cultivation. The emulsification index (EI 24 ) against coconut oil was found to be 88.42 ± 0.5%, and cell surface hydrophobicity of P. aeruginosa AMB AS7 was obtained 32.4 ± 0.9%. FTIR and GC-MS analysis revealed that the biosurfactant is rhamnolipid with anionic charge. The critical micelle concentration (CMC) of rhamnolipid was found to be 50 mg/L. It was found that 66.95% of chromium from aqueous solution can be removed using rhamnolipid at its CMC.

Enhanced production of poly(3-hydroxybutyrate) in a novel airlift reactor with in situ cell retention using Azohydromonas australica.

PubMed

Gahlawat, Geeta; Sengupta, Bedoshree; Srivastava, Ashok K

2012-09-01

Economic production of biodegradable plastics is a challenge particularly because of high substrate and energy cost inputs for its production. Research efforts are being directed towards innovations to minimize both of the above costs to economize polyhydroxybutyrate (PHB) production. A novel airlift reactor (ALR) with outer aeration and internal settling was utilized in this investigation. Although it featured no power consumption for agitation, it facilitated increased oxygen transfer rate and better cell retention than stirred tank reactor (STR), thereby resulting in enhanced PHB productivity. ALR with in situ cell retention demonstrated a significant improvement in biomass concentration and biopolymer accumulation. The total PHB production rate, specific biomass, and product yield in the ALR were observed to be 0.84 g/h, 0.43 g/g, and 0.32 g/g, respectively. The studies revealed that the volumetric oxygen mass transfer rate and mixing time for ALR were 0.016 s⁻¹ and 3.73 s, respectively, at 2.0 vvm as compared with corresponding values of 0.005 s⁻¹ and 4.95 s, respectively, in STR. This demonstrated that ALR has better oxygen mass transfer and mixing efficiency than STR. Hence, ALR with cell retention would serve as a better bioreactor design for economic biopolymer production than STR, particularly due to its lower cost of operation and simplicity along with its enhanced oxygen and heat transfer rates.

Pichia pastoris: a recombinant microfactory for antibodies and human membrane proteins.

PubMed

Gonçalves, A M; Pedro, A Q; Maia, C; Sousa, F; Queiroz, J A; Passarinha, L A

2013-05-01

During the last few decades, it has become evident that the compatibility of the yeast biochemical environment with the ability to process and translate the RNA transcript, along with its capacity to modify a translated protein, are relevant requirements for selecting this host cell for protein expression in several pharmaceutical and clinical applications. In particular, Pichia pastoris is used as an industrial host for recombinant protein and metabolite production, showing a powerful capacity to meet required biomolecular target production levels in high-throughput assays for functional genomics and drug screening. In addition, there is a great advantage to using P. pastoris for protein secretion, even at high molecular weights, since the recovery and purification steps are simplified owing to relatively low levels of endogenous proteins in the extracellular medium. Clearly, no single microexpression system can provide all of the desired properties for human protein production. Moreover, chemical and physical bioprocess parameters, including culture medium formulation, temperature, pH, agitation, aeration rates, induction, and feeding strategies, can highly influence product yield and quality. In order to benefit from the currently available wide range of biosynthesis strategies using P. pastoris, this mini review focuses on the developments and technological fermentation achievements, providing both a comparative and an overall integration analysis. The main aim is to highlight the relevance and versatility of the P. pastoris biosystem to the design of more cost-effective microfactories to meet the increasing demands for recombinant membrane proteins and clinical antibodies for several therapeutic applications.

The effect of airflow rates and aeration mode on the respiration activity of four organic wastes: Implications on the composting process.

PubMed

Mejias, Laura; Komilis, Dimitrios; Gea, Teresa; Sánchez, Antoni

2017-07-01

The aim of this study was to assess the effect of the airflow and of the aeration mode on the composting process of non-urban organic wastes that are found in large quantities worldwide, namely: (i) a fresh, non-digested, sewage sludge (FSS), (ii) an anaerobically digested sewage sludge (ADSS), (iii) cow manure (CM) and (iv) pig sludge (PS). This assessment was done using respirometric indices. Two aeration modes were tested, namely: (a) a constant air flowrate set at three different initial fixed airflow rates, and (b) an oxygen uptake rate (OUR)-controlled airflow rate. The four wastes displayed the same behaviour namely a limited biological activity at low aeration, while, beyond a threshold value, the increase of the airflow did not significantly increase the dynamic respiration indices (DRI 1 max , DRI 24 max and AT 4 ). The threshold airflow rate varied among wastes and ranged from 42NL air kg -1 DMh -1 for CM and from 67 to 77NL air kg -1 DMh -1 for FSS, ADSS and PS. Comparing the two aeration modes tested (constant air flow, OUR controlled air flow), no statistically significant differences were calculated between the respiration activity indices obtained at those two aeration modes. The results can be considered representative for urban and non-urban organic wastes and establish a general procedure to measure the respiration activity without limitations by airflow. This will permit other researchers to provide consistent results during the measurement of the respiration activity. Results indicate that high airflows are not required to establish the maximum respiration activity. This can result in energy savings and the prevention of off-gas treatment problems due to the excessive aeration rate in full scale composting plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modelling the link amongst fine-pore diffuser fouling, oxygen transfer efficiency, and aeration energy intensity.

PubMed

Garrido-Baserba, Manel; Sobhani, Reza; Asvapathanagul, Pitiporn; McCarthy, Graham W; Olson, Betty H; Odize, Victory; Al-Omari, Ahmed; Murthy, Sudhir; Nifong, Andrea; Godwin, Johnnie; Bott, Charles B; Stenstrom, Michael K; Shaw, Andrew R; Rosso, Diego

2017-03-15

This research systematically studied the behavior of aeration diffuser efficiency over time, and its relation to the energy usage per diffuser. Twelve diffusers were selected for a one year fouling study. Comprehensive aeration efficiency projections were carried out in two WRRFs with different influent rates, and the influence of operating conditions on aeration diffusers' performance was demonstrated. This study showed that the initial energy use, during the first year of operation, of those aeration diffusers located in high rate systems (with solids retention time - SRT-less than 2 days) increased more than 20% in comparison to the conventional systems (2 > SRT). Diffusers operating for three years in conventional systems presented the same fouling characteristics as those deployed in high rate processes for less than 15 months. A new procedure was developed to accurately project energy consumption on aeration diffusers; including the impacts of operation conditions, such SRT and organic loading rate, on specific aeration diffusers materials (i.e. silicone, polyurethane, EPDM, ceramic). Furthermore, it considers the microbial colonization dynamics, which successfully correlated with the increase of energy consumption (r 2 :0.82 ± 7). The presented energy model projected the energy costs and the potential savings for the diffusers after three years in operation in different operating conditions. Whereas the most efficient diffusers provided potential costs spanning from 4900 USD/Month for a small plant (20 MGD, or 74,500 m 3 /d) up to 24,500 USD/Month for a large plant (100 MGD, or 375,000 m 3 /d), other diffusers presenting less efficiency provided spans from 18,000USD/Month for a small plant to 90,000 USD/Month for large plants. The aim of this methodology is to help utilities gain more insight into process mechanisms and design better energy efficiency strategies at existing facilities to reduce energy consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

Linking biofilm growth to fouling and aeration performance of fine-pore diffuser in activated sludge.

PubMed

Garrido-Baserba, Manel; Asvapathanagul, Pitiporn; McCarthy, Graham W; Gocke, Thomas E; Olson, Betty H; Park, Hee-Deung; Al-Omari, Ahmed; Murthy, Sudhir; Bott, Charles B; Wett, Bernhard; Smeraldi, Joshua D; Shaw, Andrew R; Rosso, Diego

2016-03-01

Aeration is commonly identified as the largest contributor to process energy needs in the treatment of wastewater and therefore garners significant focus in reducing energy use. Fine-pore diffusers are the most common aeration system in municipal wastewater treatment. These diffusers are subject to fouling and scaling, resulting in loss in transfer efficiency as biofilms form and change material properties producing larger bubbles, hindering mass transfer and contributing to increased plant energy costs. This research establishes a direct correlation and apparent mechanistic link between biofilm DNA concentration and reduced aeration efficiency caused by biofilm fouling. Although the connection between biofilm growth and fouling has been implicit in discussions of diffuser fouling for many years, this research provides measured quantitative connection between the extent of biofouling and reduced diffuser efficiency. This was clearly established by studying systematically the deterioration of aeration diffusers efficiency during a 1.5 year period, concurrently with the microbiological study of the biofilm fouling in order to understand the major factors contributing to diffuser fouling. The six different diffuser technologies analyzed in this paper included four different materials which were ethylene-propylene-diene monomer (EPDM), polyurethane, silicone and ceramic. While all diffusers foul eventually, some novel materials exhibited fouling resistance. The material type played a major role in determining the biofilm characteristics (i.e., growth rate, composition, and microbial density) which directly affected the rate and intensity at what the diffusers were fouled, whereas diffuser geometry exerted little influence. Overall, a high correlation between the increase in biofilm DNA and the decrease in αF was evident (CV < 14.0 ± 2.0%). By linking bacterial growth with aeration efficiency, the research was able to show quantitatively the causal connection between bacterial fouling and energy wastage during aeration. Copyright © 2015 Elsevier Ltd. All rights reserved.

ENHANCED BIODEGRADATION THROUGH IN-SITU AERATION

EPA Science Inventory

This presentation provided an overview of enhanced aerobic bioremediation using in-situ aeration or venting. The following topics were covered: (1) Basic discussion on biodegradation and respiration testing; (2) Basic discussion on volatilization, rate-limited mass transport, an...

DESIGN INFORMATION ON FINE PORE AERATION SYSTEMS

EPA Science Inventory

Field studies were conducted over several years at municipal wastewater treatment plants employing line pore diffused aeration systems. These studies were designed to produce reliable information on the performance and operational requirements of fine pore devices under process ...

Thermal Response Of An Aerated Concrete Wall With Micro-Encapsulated Phase Change Material

NASA Astrophysics Data System (ADS)

Halúzová, Dušana

2015-06-01

For many years Phase Change Materials (PCM) have attracted attention due to their ability to store large amounts of thermal energy. This property makes them a candidate for the use of passive heat storage. In many applications, they are used to avoid the overheating of the temperature of an indoor environment. This paper describes the behavior of phase change materials that are inbuilt in aerated concrete blocks. Two building samples of an aerated concrete wall were measured in laboratory equipment called "twin-boxes". The first box consists of a traditional aerated concrete wall; the second one has additional PCM micro-encapsulated in the wall. The heat flux through the wall was measured and compared to simulation results modeled in the ESP-r program. This experimental measurement provides a foundation for a model that can be used to analyze further building constructions.

Single chamber microbial fuel cell with Ni-Co cathode

NASA Astrophysics Data System (ADS)

Włodarczyk, Barbara; Włodarczyk, Paweł P.; Kalinichenko, Antonina

2017-10-01

The possibility of wastewater treatment and the parallel energy production using the Ni-Co alloy as cathode catalyst for single chamber microbial fuel cells is presented in this research. The research included a preparation of catalyst and comparison of COD, NH4+ and NO3- reduction in the reactor without aeration, with aeration and with using a single chamber microbial fuel cell with Ni-Co cathode. The reduction time for COD with the use of microbial fuel cell with the Ni-Co catalyst is similar to the reduction time with aeration. The current density (2.4 A·m-2) and amount of energy (0.48 Wh) obtained in MFC is low, but the obtained amount of energy allows elimination of the energy needed for reactor aeration. It has been shown that the Ni-Co can be used as cathode catalyst in single chamber microbial fuel cells.

[Research of aeration with bio-film technology to treat urban landscape water].

PubMed

Song, Ying-Wei; Nie, Zhi-Dan; Nian, Yue-Gang; Huang, Min-Sheng; Huang, Jian-Jun; Yan, Hai-Hong; Zhang, Yang

2008-01-01

Research of the aeration with bio-film technology was carried out to treat scenic water of a sanatorium in Beijing. The aim of the research was improving the water habitat by increasing the transparency and reducing the concentration of N and P. The equipments were set in a 5,000 m2 water area, which combined the plug flow jet aerator with the elastic biological filler. The research indicated that the transparency increased from 25 cm to 120 cm by the technology. The removal efficiencies of NH4(+)-N, NO3(-)-N and TP were 86.6% , 90% and 73.3%, but there was only 22.4% for TN. The concentration of DO increased from 4.3 mg/L to 7 mg/L. In a word, the aeration with bio-film technology was an effective measure to improve the water habitat by increasing the transparency.

Nitrous oxide from aerated dairy manure slurries: Effects of aeration rates and oxic/anoxic phasing.

PubMed

Molodovskaya, Marina; Singurindy, Olga; Richards, Brian K; Steenhuis, Tammo S

2008-12-01

Small-scale laboratory research was conducted to compare the effects of different aeration rates and oxic/anoxic phasing on nitrous oxide (N(2)O) formation from dairy manure slurries. Manure slurry samples were incubated in triplicate for three-weeks under a range of continuous sweep gas flows (0.01-0.23L min(-1)kg(-1) slurry) with and without oxygen (air and dinitrogen gas). The net release of N(2)O-N was affected by both aeration rates and oxic/anoxic conditions, whereas ammonia volatilization depended mainly on gas flow rates. Maximum N(2)O-N losses after three-weeks incubation were 4.2% of total slurry N. Major N losses (up to 50% of total slurry N) were caused by ammonia volatilization that increased with increasing gas flow rates. The lowest nitrous oxide and ammonia production was observed from low flow phased oxic/anoxic treatment.

Thermal Bridge Effect of Aerated Concrete Block Wall in Cold Regions

NASA Astrophysics Data System (ADS)

Li, Baochang; Guo, Lirong; Li, Yubao; Zhang, Tiantian; Tan, Yufei

2018-01-01

As a self-insulating building material which can meet the 65 percent energy-efficiency requirements in cold region of China, aerated concrete blocks often go moldy, frost heaving, or cause plaster layer hollowing at thermal bridge parts in the extremely cold regions due to the restrictions of environmental climate and construction technique. L-shaped part and T-shaped part of aerated concrete walls are the most easily influenced parts by thermal bridge effect. In this paper, a field test is performed to investigate the scope of the thermal bridge effect. Moreover, a heat transfer calculation model for L-shaped wall and T-shaped wall is developed. According to the simulation results, the temperature fields of the thermal bridge affected regions are simulated and analyzed. The research outputs can provide theoretical basis for the application of aerated concrete wall in extremely cold regions.

Prediction of alpha factor values for fine pore aeration systems.

PubMed

Gillot, S; Héduit, A

2008-01-01

The objective of this work was to analyse the impact of different geometric and operating parameters on the alpha factor value for fine bubble aeration systems equipped with EPDM membrane diffusers. Measurements have been performed on nitrifying plants operating under extended aeration and treating mainly domestic wastewater. Measurements performed on 14 nitrifying plants showed that, for domestic wastewater treatment under very low F/M ratios, the alpha factor is comprised between 0.44 and 0.98. A new composite variable (the Equivalent Contact Time, ECT) has been defined and makes it possible for a given aeration tank, knowing the MCRT, the clean water oxygen transfer coefficient and the supplied air flow rate, to predict the alpha factor value. ECT combines the effect on mass transfer of all generally accepted factors affecting oxygen transfer performances (air flow rate, diffuser submergence, horizontal flow). (c) IWA Publishing 2008.

Exploring the effect of foot massage on agitated behaviours in older people with dementia: a pilot study.

PubMed

Moyle, Wendy; Johnston, Amy Nicole Burne; O'Dwyer, Siobhan Therese

2011-09-01

To explore the effects of foot massage on agitated behaviours in older people with dementia living in long-term care. Seventeen men and 5 women (mean age 84.7 years), with a diagnosis of dementia and a history of clinically significant agitation, received a 10-minute foot massage each day for 14 days. The short form of the Cohen-Mansfield Agitation Inventory (CMAI-SF) and the Revised Memory and Behavior Problems Checklist (RMBPC) were completed at baseline, post-test and 2-weeks follow up. CMAI-SF and RMBPC scores were significantly reduced at post-test and remained significantly lower than baseline at follow up. This study provides preliminary evidence suggesting that limited short-duration foot massage reduces agitation and related behavioural problems in people with dementia, and that these behaviour changes are maintained after the massage ceases. A randomised controlled trial is required to confirm these findings. © 2011 The Authors. Australasian Journal on Ageing © 2011 ACOTA.

Wernicke encephalopathy without delirium that appeared as agitation in a patient with lung cancer.

PubMed

Onishi, Hideki; Ishida, Mayumi; Takahashi, Takao; Taji, Yoshitada; Ikebuchi, Kenji; Furuya, Daisuke; Uchida, Nozomu; Akechi, Tatsuo

2018-05-11

Wernicke encephalopathy (WE) is a neuropsychiatric disorder caused by thiamine deficiency, and is sometimes overlooked because of the diversity of clinical symptoms. From a series of WE patients with cancer, we report a lung cancer patient who developed WE, the main symptom of which was agitation.ResultA 50-year-old woman with lung cancer was referred to our psycho-oncology clinic because of agitation lasting for three days. No laboratory findings or drugs explaining her agitation were identified. Although the patient did not develop delirium, ophthalmoplegia, or ataxia, WE was suspected because she experienced a loss of appetite loss lasting 5 weeks. This diagnosis was supported by abnormal serum thiamine and disappearance of agitation one hour after intravenous thiamine administration.Significance of resultsThis report emphasizes the clinical diversity of WE and indicates the limits of the ability to diagnose WE from typical clinical symptoms. The presence of a loss of appetite for more than two weeks may be the key to the accurate diagnosis of WE.

Association of plasma homovanillic acid with behavioral symptoms in patients diagnosed with dementia: a preliminary report.

PubMed

Sweet, R A; Pollock, B G; Mulsant, B H; Rosen, J; Lo, K H; Yao, J K; Henteleff, R A; Mazumdar, S

1997-12-01

Neuroleptic treatment of psychotic symptoms or agitated behavior in elderly patients diagnosed with dementia is associated with reduced efficacy and increased rates of neuroleptic-induced parkinsonism in comparison to younger patients with schizophrenia. We report the first study to examine the relationship between an in vivo measure of dopaminergic function, plasma homovanillic acid (pHVA), and ratings of psychosis, agitation, and parkinsonism before and after neuroleptic treatment in dementia patients. Pretreatment pHVA was significantly correlated with parkinsonian rigidity, with a trend observed with agitation and hostility. Though mean pHVA did not change during perphenazine treatment, intraindividual change in pHVA at day 15 was correlated with improvement in hostility, with a similar trend for improvement in agitation. These preliminary findings are consistent with reports associating dopaminergic function with agitated, but not psychotic, symptoms in patients diagnosed with dementia, and with a reduced responsivity of dopaminergic systems to neuroleptic treatment in these patients.

[Drug management of agitation in emergency departments: theoretical recommendations and studies of practices].

PubMed

Horn, Mathilde; Vaiva, Guillaume; Dumais, Alexandre

2015-01-01

Management of agitation is a frequent problematic of emergency departments that often leads to feelings of insecurity among clinicians. There are various practices regarding the drugs to be used in the management of agitations. Guidelines have been proposed by different groups of experts concerning the antipsychotic drugs that should be used for agitations in psychiatric conditions. Nevertheless, there is no clear-cut procedure referring to the utilization of intramuscular drugs in this situation. Moreover, there is no comparison available between the commonly used medications and other drugs, both in terms of superiority of efficacy and tolerance. In order to accurately assess these practices, evaluation protocols must minimize the interference with the service organization and the routine care. Further studies are required in order to develop guidelines about medications that have to be used to handle agitations, which must be based on robust evidence and applicable to emergency services. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Design of top covers supporting aerobic in situ stabilization of old landfills--an experimental simulation in lysimeters.

PubMed

Hrad, Marlies; Huber-Humer, Marion; Wimmer, Bernhard; Reichenauer, Thomas G

2012-12-01

Landfill aeration by means of low pressure air injection is a promising tool to reduce long term emissions from organic waste fractions through accelerated biological stabilization. Top covers that enhance methane oxidation could provide a simple and economic way to mitigate residual greenhouse gas emissions from in situ aerated landfills, and may replace off-gas extraction and treatment, particularly at smaller and older sites. In this respect the installation of a landfill cover system adjusted to the forced-aerated landfill body is of great significance. Investigations into large scale lysimeters (2 × 2 × 3m) under field conditions have been carried out using different top covers including compost materials and natural soils as a surrogate to gas extraction during active low pressure aeration. In the present study, the emission behaviour as well as the water balance performance of the lysimeters has been investigated, both prior to and during the first months of in situ aeration. Results reveal that mature sewage sludge compost (SSC) placed in one lysimeter exhibits in principle optimal ambient conditions for methanotrophic bacteria to enhance methane oxidation. Under laboratory conditions the mature compost mitigated CH(4) loadings up to 300 lCH(4)/m(2)d. In addition, the compost material provided high air permeability even at 100% water holding capacity (WHC). In contrast, the more cohesive, mineral soil cover was expected to cause a notably uniform distribution of the injected air within the waste layer. Laboratory results also revealed sufficient air permeability of the soil materials (TS-F and SS-Z) placed in lysimeter C. However, at higher compaction density SS-Z became impermeable at 100% WHC. Methane emissions from the reference lysimeter with the smaller substrate cover (12-52 g CH(4)/m(2)d) were significantly higher than fluxes from the other lysimeters (0-19 g CH(4)/m(2)d) during in situ aeration. Regarding water balance, lysimeters covered with compost and compost-sand mixture, showed the lowest leachate rate (18-26% of the precipitation) due to the high water holding capacity and more favourable plant growth conditions compared to the lysimeters with mineral, more cohesive, soil covers (27-45% of the precipitation). On the basis of these results, the authors suggest a layered top cover system using both compost material as well as mineral soil in order to support active low-pressure aeration. Conventional soil materials with lower permeability may be used on top of the landfill body for a more uniform aeration of the waste due to an increased resistance to vertical gas flow. A compost cover may be built on top of the soil cover underlain by a gas distribution layer to improve methane oxidation rates and minimise water infiltration. By planting vegetation with a high transpiration rate, the leachate amount emanating from the landfill could be further minimised. The suggested design may be particularly suitable in combination with intermittent in situ aeration, in the later stage of an aeration measure, or at very small sites and shallow deposits. The top cover system could further regulate water infiltration into the landfill and mitigate residual CH(4) emissions, even beyond the time of active aeration. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biological treatment of soils contaminated with hydrophobic organics using slurry- and solid-phase techniques

NASA Astrophysics Data System (ADS)

Cassidy, Daniel H.; Irvine, Robert L.

1995-10-01

Both slurry-phase and solid-phase bioremediation are effective ex situ soil decontamination methods. Slurrying is energy intensive relative to solid-phase treatment, but provides homogenization and uniform nutrient distribution. Limited contaminant bioavailability at concentrations above the required cleanup level reduces biodegradation rates and renders solid phase bioremediation more cost effective than complete treatment in a bio-slurry reactor. Slurrying followed by solid-phase bioremediation combines the advantages and minimizes the weaknesses of each treatment method when used alone. A biological treatment system consisting of slurrying followed by aeration in solid phase bioreactors was developed and tested in the laboratory using a silty clay loam contaminated with diesel fuel. The first set of experiments was designed to determine the impact of the water content and mixing time during slurrying on the rate an extent of contaminant removal in continuously aerated solid phase bioreactors. The second set of experiments compared the volatile and total diesel fuel removal in solid phase bioreactors using periodic and continuous aeration strategies. Results showed that slurrying for 1.5 hours at a water content less than saturation markedly increased the rate and extent of contaminant biodegradation in the solid phase bioreactors compared with soil having no slurry pretreatment. Slurrying the soil at or above its saturation moisture content resulted in lengthy dewatering times which prohibited aeration, thereby delaying the onset of biological treatment in the solid phase bioreactors. Results also showed that properly operated periodic aeration can provide less volatile contaminant removal and a grater fraction of biological contaminant removal than continuous aeration.

Inorganic nitrogen transformations in the treatment of landfill leachate with a high ammonium load: A case study.

PubMed

Parkes, Stephen D; Jolley, Dianne F; Wilson, Stephen R

2007-01-01

The inorganic nitrogen transformations occurring at a municipal waste leachate treatment facility were investigated. The treatment facility consisted of a collection well and an artificial wetland between two aeration ponds. The first aeration pond showed a decrease in ammonium (from 3480 (+/- 120) to 630(+/- 90) mg x L(-1)), a reduction in inorganic nitrogen load (3480 to 1680 mg N x L(-1)), and an accumulation of nitrite (< 1.3 mg-N x L(-1) in the collection well, to 1030 mg-N x L(-1)). Incomplete ammonium oxidation was presumably the result of the low concentration of carbonate alkalinity (approximately 2 mg x L(-1)), which may cause a limitation in the ammonium oxidation rate of nitrifiers. Low carbonate alkalinity levels may have been the result of stripping of CO(2) from the first aeration pond at the high aeration rates and low pH. Various chemodenitrification mechanisms are discussed as the reason for the reduction in the inorganic nitrogen load, including; the reduction of nitrite by iron (II) (producing various forms of gaseous nitrogen); and reactions involving nitrous acid. It is suggested that the accumulation of nitrite may be the result of inhibition of nitrite oxidizers by nitrous acid and low temperatures. Relative to the first aeration pond, the speciation and concentration of inorganic nitrogen was stable in the wetlands and 2nd aeration pond. The limited denitrification in the wetlands most probably occurred due to low concentrations of organic carbon, and short retention times.

EMMC process for combined removal of organics, nitrogen and an odor producing substance.

PubMed

Yang, P Y; Su, R; Kim, S J

2003-12-01

In order to improve the process performance regarding the removal of organics, nitrogen, and an odor-causing compound (sulfide) contained in domestic wastewater, an entrapped-mixed-microbial cell (EMMC) with and without humic substances for both fixed and moving carrier reactors and conventional suspended growth culture (i.e. conventional activated sludge process) were investigated simultaneously. Both synthetic (simulated to the organics concentration of general domestic sewage) and actual domestic wastewater were investigated under operational conditions of 12 h of hydraulic retention time (HRT) with 1 h of aeration and 1 h of non-aeration, and 6 h of HRT with continuous aeration, at a room temperature of 25 +/- 2 degrees C. It was found that entrapping humic substances in the EMMC carriers had no impact on the removal of organics, nitrogen, and the odor-producing compound. Additionally, the performance of the EMMC moving carrier system for the removal of these pollutants is similar to that of the EMMC fixed carrier system. In general, the EMMC associated systems which provide high solids retention time achieve a better removal of chemical oxygen demand (COD), nitrogen, and the odor-producing substance than the suspended growth system for both HRTs of 6 h (continuous aeration) and 12 h (1 h of aeration and 1 h of non-aeration). Both the fixed and moving carrier EMMC processes, therefore, have the potential for improvement or replacement of the existing conventional activated sludge process with regard to improving the effluent qualities (such as COD, nitrogen and odor-producing compound) for reuse/disposal.

Oxygen microprofiles within the sediment-water interface studied by optode and its implication for aeration of polluted urban rivers.

PubMed

Liu, Bo; Han, Rui-Ming; Wang, Wen-Lin; Yao, Hong; Zhou, Feng

2017-04-01

To reveal the detailed vertical oxygen distribution at the sediment-water interface (SWI) and its relation with the oxygen consumption processes during and after aeration of polluted urban rivers, experimental systems constructed with collected sediment and in situ overlying water from a polluted urban river were aerated above or beneath the sediment-water interface 12 h a day for 15 days and left nonaerated for the following 10 days. The results showed that aeration of water or sediment both increased dissolved oxygen (DO) concentrations in the SWI, characterized by shifts in a "decrease-increase-decrease" manner during around 3 h for the aeration of water treatment (AW) and 6 h for the aeration of sediment treatment (AS). The oxygen penetration depth for AS experiments was between 0.66 and 4.16 mm with an average of 1.79 mm, significantly higher than that for AW experiments; however, the oxygen dissipation constant (mm -1 ) measuring the decay rate of DO near the SWI was greater for the AW experiments than the AS experiments. During the 10-day nonaeration period, the accumulation of nitrate in both the overlying water and sediment was greatly increased concomitantly with the higher oxygenation in AS experiments. From the nitrogen removal viewpoint, these results suggest that the SWI needs moderate oxygenation which enables nitrate and nitrite to be removed by denitrification rather than to be totally nitrified and accumulate as would result from the conventional practice by singly elevating DO concentrations.

Combination of Methoprene and Controlled Aeration to Manage Insects in Stored Wheat.

PubMed

Liu, Samuel S; Arthur, Frank H; VanGundy, Douglas; Phillips, Thomas W

2016-06-17

A commercial formulation of the insect growth regulator methoprene was applied to wheat stored in small bins either alone or in combination with controlled aeration of the bins, to lower grain temperature for insect pest management of stored wheat. Grain temperatures were monitored and modified by a computer-controlled thermocouple system that also activated the aeration system at programmed set-points to move cool ambient air through the grain mass to lower grain temperature. Results from sampling insect populations in experimental storage bins along with laboratory mortality bioassays of insects placed on wheat taken from the bins over the course of the storage period showed that methoprene was very effective in controlling infestation by the externally-feeding stored grain insects Plodia interpunctella (Hübner), the Indian meal moth Tribolium castaneum (Herbst), the red flour beetle, Cryptolestes ferrugineus (Stephens), the rusty grain beetle, and also for the internal-feeding pest Rhyzopertha dominica( Fauvel), the lesser grain borer. Methoprene did not give good control of the internal-feeding pest Sitophilus oryzae (L.), the rice weevil. Aeration alone was somewhat effective in suppressing insect population development, while methoprene alone or when combined with aeration greatly enhanced insect control. Commercial grain grading for industry quality standards at the end of the storage period confirmed the impact of insect suppression on maintaining high quality of the stored wheat. This field experiment shows that methoprene combined with aeration to cool grain can be effective for pest management of stored wheat in the southern plains of the United States of America.

Proof of live birth using postmortem multislice computed tomography (pmMSCT) in cases of suspected neonaticide: advantages of diagnostic imaging compared to conventional autopsy.

PubMed

Guddat, Saskia S; Gapert, René; Tsokos, Michael; Oesterhelweg, Lars

2013-03-01

Proof of live birth is of major importance in suspected neonaticide cases. Although not without controversy the lung flotation test is the main method used to asses this in different jurisdictions worldwide. The present study examines the usefulness of postmortem multislice computed tomography (pmMSCT) in the detection of live birth signs. Body scans were conducted on four infants, one was stillborn, another died a day after birth and the other two were classified as neonaticides. The appearance of the lungs, gastrointestinal tract and vascular system of the liver was compared in these cases. Clear differences were discernable between the lungs of the stillborn and the 1 day old infant. The aerated lungs and air in the stomach and duodenum were clearly visible in the latter case while the stillborn infant lacked these signs. The two neonaticide cases demonstrated similarly aerated lung tissue to the 1 day old infant. The hepatic vessels did not show any putrefactive gas changes in any of the cases. The extent of aeration of the peripheral alveoli was easily observable on the pmMSCT, thus making it a useful tool in the possible differentiation between artificially and naturally aerated lungs. During the four autopsies the classic flotation tests were performed and similar positive aeration of the lungs in the two neonaticides was shown. The stillborn's tests, on the other hand were negative for aeration. The results of this study clearly demonstrate the advantages of using pmMSCT before commencing a conventional autopsy in cases of suspected neonaticide.

Severity of Neuropsychiatric Symptoms in Nursing Home Residents.

PubMed

Helvik, Anne-Sofie; Engedal, Knut; Wu, Bei; Benth, Jūratė Šaltytė; Corazzini, Kirsten; Røen, Irene; Selbæk, Geir

2016-01-01

We aimed at assessing time shift in the severity of neuropsychiatric symptoms (NPS) in nursing home residents between 2004/2005 and 2010/2011 and associations between NPS and socio-demographic variables, physical health status, dementia severity, and the use of psychotropic drugs. The Neuropsychiatric Inventory Nursing Home Version was used in 2004/2005 (n = 1,163) and 2010/2011 (n = 1,858). Linear mixed model analysis was applied. There was no time shift in the severity of apathy, psychosis, and affective symptoms, but agitation did exhibit a time shift. Agitation was less severe in 2010/2011 than in 2004/2005 in residents with a Clinical Dementia Rating (CDR) sum of boxes score ≤4, and more severe in residents with a CDR sum of boxes score >16. Higher CDR sum of boxes scores and use of psychotropic medication were associated with more severe apathy, agitation, psychosis, and affective symptoms. Poor physical health was associated with more severe apathy, psychosis, and affective symptoms. Women had more severe agitation and less severe affective symptoms than men. A longer stay in a nursing home was associated with more severe agitation and less severe affective symptoms. In conclusion, agitation was less severe in 2010/2011 than in 2004/2005 among nursing home residents with a milder degree of dementia, and more severe in residents with severe dementia.

Effect of Pore Clogging on Kinetics of Lead Uptake by Clinoptilolite.

PubMed

Inglezakis; Diamandis; Loizidou; Grigoropoulou

1999-07-01

The kinetics of lead-sodium ion exchange using pretreated natural clinoptilolite are investigated, more specifically the influence of agitation (0, 210, and 650 rpm) on the limiting step of the overall process, for particle sizes of 0.63-0.8 and 0.8-1 mm at ambient temperature and initial lead solutions of 500 mg l-1 without pH adjustment. The isotopic exchange model is found to fit the ion exchange process. Particle diffusion is shown to be the controlling step for both particle sizes under agitation, while in the absence of agitation film diffusion is shown to control. The ion exchange process effective diffusion coefficients are calculated and found to depend strongly on particle size in the case of agitation at 210 rpm and only slightly on particle size at 650 rpm. Lead uptake rates are higher for smaller particles only at rigorous agitation, while at mild agitation the results are reversed. These facts are due to partial clogging of the pores of the mineral during the grinding process. This is verified through comparison of lead uptake rates for two samples of the same particle size, one of which is rigorously washed for a certain time before being exposed to the ion exchange. Copyright 1999 Academic Press.

Knowledge and Attitude Towards Pharmacological Management of Acute Agitation: A Survey of Psychiatrists, Psychiatry Residents, and Psychiatric Nurses.

PubMed

Tangu, KeumbÔh; Ifeanyi, Adaora; Velusamy, Mayurapriya; Dar, Sara; Shah, Nurun; Ezeobele, Ifeoma E; Okusaga, Olaoluwa O

2017-06-01

The authors compared the current knowledge and attitude of psychiatrists, psychiatry residents, and psychiatric nurses towards the pharmacological management of acute agitation. Questionnaires were electronically distributed to all attending psychiatrists, psychiatry residents, and psychiatric nurses who were either employed by the University Department of Psychiatry and Behavioral Sciences or were staff at a 250-bed affiliated Psychiatric Hospital. Where possible, Fisher's exact test was used to compare responses to questions based on designation. Of the 250 questionnaires distributed, 112 were returned (response rate of 44.8%), of which 64 (57.1%) were psychiatric nurses, 27 (24.1%) were attending psychiatrists, and 21 (18.8%) were psychiatry residents. A significantly higher percentage of attending psychiatrists and psychiatric nurses compared to psychiatry residents thought that newer second- generation antipsychotics (SGAs) are not as effective as older first-generation antipsychotics (FGAs) for managing acute agitation (55.6, 48.4, and 9.5% respectively, p = 0.008). The combination of intramuscular haloperidol, lorazepam, and diphenhydramine was the most preferred option chosen by all designations for the psychopharmacological management of severe agitation. Furthermore, a larger percentage of the psychiatric nurses, in comparison to attending psychiatrists, also chose the combination of intramuscular chlorpromazine, lorazepam, and diphenhydramine as an option for managing severe agitation; no psychiatry resident chose this option. Knowledge of evidence-based psychopharmacological management of agitation differs among attending psychiatrists, psychiatry residents and psychiatric nurses. Although the management of agitation should be individualized and context specific, monotherapy should be considered first where applicable.

The Effect of Diode Laser With Different Parameters on Root Fracture During Irrigation Procedure.

PubMed

Karataş, Ertuğrul; Arslan, Hakan; Topçuoğlu, Hüseyin Sinan; Yılmaz, Cenk Burak; Yeter, Kübra Yesildal; Ayrancı, Leyla Benan

2016-06-01

The aim of this study is to compare the effect of a single diode laser application and agitation of EDTA with diode laser with different parameters at different time intervals on root fracture. Ninety mandibular incisors were instrumented except the negative control group. The specimens were divided randomly into 10 groups according to final irrigation procedure: (G1) non-instrumented; (G2) distilled water; (G3) 15% EDTA; (G4) ultrasonically agitated EDTA; (G5) single 1.5W/100 Hz Diode laser; (G6) single 3W/100 Hz Diode laser; (G7) 1.5W/100 Hz Diode laser agitation of EDTA for 20 s; (G8) 1.5W/100 Hz Diode laser agitation of EDTA for 40 s; (G9) 3W/100 Hz Diode laser agitation of EDTA for 20 s; and (G10) 3W/100 Hz Diode laser agitation of EDTA for 40 s. The specimens were filled, mounted in acrylic resin, and compression strength test was performed on each specimen. Statistical analysis was carried out using one way ANOVA and Tukey's post hoc tests (P = 0.05). The statistical analysis revealed that there were statistically significant differences among the groups (P < 0.05). Laser-agitated irrigation with a 3W/100 Hz Diode laser for both 20 s and 40 s decreased the fracture resistance of teeth. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

INVESTIGATIONS INTO BIOFOULING PHENOMENA IN FINE PORE AERATION DEVICES

EPA Science Inventory

Microbiologically-based procedures were used to describe biofouling phenomena on fine pore aeration devices and to determine whether biofilm characteristics could be related to diffuser process performance parameters. Fine pore diffusers were obtained from five municipal wastewa...

T.A. BROWN MECHANICAL AERATOR

EPA Science Inventory

Students in the Environmental Engineering and Waster Resources capstone design class in the Department of Civil and Environmental Engineering will undertake a project in conjunction with Serasih Indonesia to develop a prototype mechanical aerator to be used in aquaculture live...

Comparison of the efficacy of aroma-acupressure and aromatherapy for the treatment of dementia-associated agitation.

PubMed

Yang, Man-Hua; Lin, Li-Chan; Wu, Shiao-Chi; Chiu, Jen-Hwey; Wang, Pei-Ning; Lin, Jaung-Geng

2015-03-29

One of the most common symptoms observed in patients with dementia is agitation, and several non-pharmacological treatments have been used to control this symptom. However, because of limitations in research design, the benefit of non-pharmacological treatments has only been demonstrated in certain cases. The purpose of this study was to compare aroma-acupressure and aromatherapy with respect to their effects on agitation in patients with dementia. In this experimental study, the participants were randomly assigned to three groups: 56 patients were included in the aroma-acupressure group, 73 patients in the aromatherapy group, and 57 patients in the control group who received daily routine as usual without intervention. The Cohen-Mansfield Agitation Inventory (CMAI) scale and the heart rate variability (HRV) index were used to assess differences in agitation. The CMAI was used in the pre-test, post-test and post-three-week test, and the HRV was used in the pre-test, the post-test and the post-three-week test as well as every week during the four-week interventions. The CMAI scores were significantly lower in the aroma-acupressure and aromatherapy groups compared with the control group in the post-test and post-three-week assessments. Sympathetic nervous activity was significantly lower in the fourth week in the aroma-acupressure group and in the second week in the aromatherapy group, whereas parasympathetic nervous activity increased from the second week to the fourth week in the aroma-acupressure group and in the fourth week in the aromatherapy group. Aroma-acupressure had a greater effect than aromatherapy on agitation in patients with dementia. However, agitation was improved in both of the groups, which allowed the patients with dementia to become more relaxed. Future studies should continue to assess the benefits of aroma-acupressure and aromatherapy for the treatment of agitation in dementia patients. ChiCTR-TRC-14004810; Date of registration: 2014/6/12.

Foot massage versus quiet presence on agitation and mood in people with dementia: a randomised controlled trial.

PubMed

Moyle, Wendy; Cooke, Marie Louise; Beattie, Elizabeth; Shum, David H K; O'Dwyer, Siobhan T; Barrett, Sue

2014-06-01

There is increasing interest in using complementary and alternative treatments to manage behavioural and psychological symptoms of dementia such as agitation, aggression and depressed mood. To compare the effect of foot massage (intervention) and quiet presence (control) on agitation and mood in people with dementia. A randomised controlled trial using a within-subjects, crossover design. Five long-term care facilities in Brisbane, Australia. The primary outcome was the Cohen-Mansfield Agitation Inventory (CMAI) and the secondary outcome was the Observed Emotion Rating Scale (OERS). The screening and data collection research assistants, families, and care staff were blinded to participant allocation. Participants of the study were 55 long-term care residents aged 74-103 years (mean age 86.5), with moderate to severe dementia and a history of agitated behaviour according to the Pittsburgh Agitation Scale. A computer-program randomised participants to 10-min foot massage (intervention) or quiet presence (control), every weekday for 3 weeks. A carry-over effect was identified in the data, and so the data was treated as a parallel groups RCT. The mean total CMAI increased in both groups (reflecting an increase in agitation) with this increase greater in the quiet presence group than the foot massage group (p=0.03). There was a trend towards a difference on OERS General Alertness, with a positive change in alertness for participants in the foot massage group (indicating reduced alertness) and a negative change for participants in the quiet presence group (indicating increased alertness) (F(1,51)=3.88, p=0.05, partial ή(2)=0.07). The findings highlight the need for further research on the specific conditions under which massage might promote relaxation and improve mood for people with dementia. The unfamiliar research assistants and variations in usual activity may have contributed to the increase in agitation and this needs further research. ACTRN12612000658819. Copyright © 2013 Elsevier Ltd. All rights reserved.

Measuring information processing in a client with extreme agitation following traumatic brain injury using the Perceive, Recall, Plan and Perform System of Task Analysis.

PubMed

Nott, Melissa T; Chapparo, Christine

2008-09-01

Agitation following traumatic brain injury is characterised by a heightened state of activity with disorganised information processing that interferes with learning and achieving functional goals. This study aimed to identify information processing problems during task performance of a severely agitated adult using the Perceive, Recall, Plan and Perform (PRPP) System of Task Analysis. Second, this study aimed to examine the sensitivity of the PRPP System to changes in task performance over a short period of rehabilitation, and third, to evaluate the guidance provided by the PRPP in directing intervention. A case study research design was employed. The PRPP System of Task Analysis was used to assess changes in task embedded information processing capacity during occupational therapy intervention with a severely agitated adult in a rehabilitation context. Performance is assessed on three selected tasks over a one-month period. Information processing difficulties during task performance can be clearly identified when observing a severely agitated adult following a traumatic brain injury. Processing skills involving attention, sensory processing and planning were most affected at this stage of rehabilitation. These processing difficulties are linked to established descriptions of agitated behaviour. Fluctuations in performance across three tasks of differing processing complexity were evident, leading to hypothesised relationships between task complexity, environment and novelty with information processing errors. Changes in specific information processing capacity over time were evident based on repeated measures using the PRPP System of Task Analysis. This lends preliminary support for its utility as an outcome measure, and raises hypotheses about the type of therapy required to enhance information processing in people with severe agitation. The PRPP System is sensitive to information processing changes in severely agitated adults when used to reassess performance over short intervals and can provide direct guidance to occupational therapy intervention to improve task embedded information processing by categorising errors under four stages of an information processing model: Perceive, Recall, Plan and Perform.

72. (Credit LSU) Aerator in settling basin south of McNeil ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

72. (Credit LSU) Aerator in settling basin south of McNeil Pumping Station c1907. (Louisiana State University in Shreveport Archives, post card collection) - McNeil Street Pumping Station, McNeil Street & Cross Bayou, Shreveport, Caddo Parish, LA

Removal of iron and manganese by artificial destratification in a tropical climate (Upper Layang Reservoir, Malaysia).

PubMed

Ismail, R; Kassim, M A; Inman, M; Baharim, N H; Azman, S

2002-01-01

Environmental monitoring was carried out at Upper Layang Reservoir situated in Masai, Johor, Malaysia. The study shows that thermal stratification and natural mixing of the water column do exist in the reservoir and the level of stratification varies at different times of the year. Artificial destratification via diffused air aeration techniques was employed at the reservoir for two months. The results show that thermal stratification was eliminated after a week of continuous aeration. The concentrations of iron and to a lesser extent manganese in the water column was also reduced during the aeration period.

Quality evaluation of carbonaceous industrial by-products and its effect on properties of autoclave aerated concrete

NASA Astrophysics Data System (ADS)

Fomina, E. V.; Lesovik, V. S.; Fomin, A. E.; Kozhukhova, N. I.; Lebedev, M. S.

2018-03-01

Argillite is a carbonaceous industrial by-product that is a potential source in environmentally friendly and source-saving construction industry. In this research, chemical and mineral composition as well as particle size distribution of argillite were studied and used to develop autoclave aerated concrete as partial substitute of quartz sand. Effect of the argillite as a mineral admixture in autoclave aerated concrete was investigated in terms of compressive and tensile strength, density, heat conductivity etc. The obtained results demonstrated an efficiency of argillite as an energy-saving material in autoclave construction composites.

Incorporation of air into a snack food reduces energy intake.

PubMed

Osterholt, Kathrin M; Roe, Liane S; Rolls, Barbara J

2007-05-01

This study investigated how the air content of a familiar snack food affected energy intake and whether varying the method of serving the snack modified intake. We tested two versions of an extruded snack (cheese puffs) that were equal in energy density (5.7 kcal/g), but differed in energy per volume (less-aerated snack: 1.00 kcal/ml; more-aerated snack: 0.45 kcal/ml). In a within-subjects design, 16 women and 12 men consumed the snacks ad libitum in the laboratory during four afternoon sessions. A standard volume (1250 ml) of each snack was served once in a bowl and once in an opaque bag. Results showed significant differences in intake of the two snacks by energy (p=0.0003) and volume (p<0.0001); subjects consumed 21% less weight and energy (70+/-17 kcal) of the more-aerated snack than the less-aerated snack, although they consumed a 73% greater volume of the more-aerated snack (239+/-24 ml). These findings suggest that subjects responded to both the weight and volume of the snack. Despite differences in intake, hunger and fullness ratings did not differ across conditions. The serving method did not significantly affect intake. Results from this study indicate that incorporating air into food provides a strategy to reduce energy intake from energy-dense snacks.

Effect of aeration rate, moisture content and composting period on availability of copper and lead during pig manure composting.

PubMed

Shen, Yujun; Zhao, Lixin; Meng, Haibo; Hou, Yueqing; Zhou, Haibin; Wang, Fei; Cheng, Hongsheng; Liu, Hongbin

2016-06-01

Pollution by heavy metals, such as copper and lead, has become a limiting factor for the land application of faecal manures, such as pig manure. This study was conducted to investigate the influence of composting process parameters, including aeration rate, moisture content and composting period, on the distribution of heavy metal species during composting, and to select an optimal parameter for copper and lead inactivation. Results showed that the distribution ratios of exchangeable fractions of copper and lead had a bigger decrease under conditions of aeration rate, 0.1 m(3) min(-1) m(-3), an initial moisture content of 65% and composting period of 50 days. Suboptimal composting process conditions could lead to increased availability of heavy metals. Statistical analysis indicated that the aeration rate was the main factor affecting copper and lead inactivation, while the effects of moisture content and composting period were not significant. The rates of reduction of copper-exchangeable fractions and lead-exchangeable fractions were positively correlated with increased pH. The optimal parameters for reducing heavy metal bioavailability during pig manure composting were aeration rate, 0.1 m(3) min(-1) m(-3), initial moisture content, 65%, and composting period, 20 days. © The Author(s) 2016.

CFD Investigation of the effects of bubble aerator layouts on hydrodynamics of an activated sludge channel reactor.

PubMed

Hreiz, Rainier; Potier, Olivier; Wicks, Jim; Commenge, Jean-Marc

2018-03-08

In this paper, computational fluid dynamics (CFD) simulations are employed to characterize the effects of bubble aerator layouts (i.e. spatial arrangement) on the hydrodynamics in activated sludge (AS) reactors. The first configuration considered is a channel reactor with aerators placed alongside one lateral wall, for which velocity measurements are available in literature. CFD results were in good agreement with experimental data, which proves that the model is sufficiently accurate and predictive. Accordingly, simulations and numerical residence time distribution tests were conducted for different aerator layouts to determine their effects on the reactor hydrodynamics. The results revealed that the flow characteristics are extremely sensitive to the aerators arrangement given the high gas flow rates used in AS processes. Among the layouts investigated, the one where diffusers are placed all over the reactor floor has led to the least dispersive flow, i.e. which characteristics best tend toward that of an ideal plug flow reactor. Indeed, this flow field presented the lowest average turbulent diffusion and the most uniform axial velocity and turbulence fields. Such a flow behaviour is expected to be highly beneficial for biological treatment since it reduces pollutant dilution by axial diffusion and limits raw wastewater channelling to the outlet.

Optimization of high-rate TN removal in a novel constructed wetland integrated with microelectrolysis system treating high-strength digestate supernatant.

PubMed

Guo, Luchen; He, Keli; Wu, Shubiao; Sun, Hao; Wang, Yanfei; Huang, Xu; Dong, Renjie

2016-08-01

The potential of high-rate TN removal in three aerated horizontal subsurface-flow constructed wetlands to treat high-strength anaerobic digestate supernatant was evaluated. Different strategies of intermittent aeration and effluent recirculation were applied to compare their effect on nitrogen depuration performance. Additional glucose supply and iron-activated carbon based post-treatment systems were established and examined, respectively, to further remove nitrate that accumulated in the effluents from aerated wetlands. The results showed that intermittent aeration (1 h on:1 h off) significantly improved nitrification with ammonium removal efficiency of 90% (18.1 g/(m(2)·d)), but limited TN removal efficiency (53%). Even though effluent recirculation (a ratio of 1:1) increased TN removal from 53% to 71%, the effluent nitrate concentration was still high. Additional glucose was used as a post-treatment option and further increased the TN removal to 82%; however, this implementation caused additional organic pollution. Furthermore, the iron-activated carbon system stimulated with a microelectrolysis process achieved greater than 85% effluent nitrate removal and resulted in 86% TN removal. Considering the high TN removal rate, aerated constructed wetlands integrated with a microelectrolysis-driven system show great potential for treating high-strength digestate supernatant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Integral parameters for characterizing water, energy, and aeration properties of soilless plant growth media

NASA Astrophysics Data System (ADS)

Chamindu Deepagoda, T. K. K.; Chen Lopez, Jose Choc; Møldrup, Per; de Jonge, Lis Wollesen; Tuller, Markus

2013-10-01

Over the last decade there has been a significant shift in global agricultural practice. Because the rapid increase of human population poses unprecedented challenges to production of an adequate and economically feasible food supply for undernourished populations, soilless greenhouse production systems are regaining increased worldwide attention. The optimal control of water availability and aeration is an essential prerequisite to successfully operate plant growth systems with soilless substrates such as aggregated foamed glass, perlite, rockwool, coconut coir, or mixtures thereof. While there are considerable empirical and theoretical efforts devoted to characterize water retention and aeration substrate properties, a holistic, physically-based approach considering water retention and aeration concurrently is lacking. In this study, the previously developed concept of integral water storage and energy was expanded to dual-porosity substrates and an analog integral oxygen diffusivity parameter was introduced to simultaneously characterize aeration properties of four common soilless greenhouse growth media. Integral parameters were derived for greenhouse crops in general, as well as for tomatoes. The integral approach provided important insights for irrigation management and for potential optimization of substrate properties. Furthermore, an observed relationship between the integral parameters for water availability and oxygen diffusivity can be potentially applied for the design of advanced irrigation and management strategies to ensure stress-free growth conditions, while conserving water resources.

Respirator triggering of electron beam computed tomography (EBCT): evaluation of dynamic changes during mechanical expiration in the traumatized patient

NASA Astrophysics Data System (ADS)

Recheis, Wolfgang A.; Kleinsasser, Axel; Hatschenberger, Robert; Knapp, Rudolf; zur Nedden, Dieter; Hoermann, Christoph

1999-05-01

The purpose of this project is to evaluate the dynamic changes during expiration at different levels of positive end- expiratory pressure (PEEP) in the ventilated patient. We wanted to discriminate between normal lung function and acute respiratory distress syndrome (ARDS). After approval by the local Ethic Committee we studied two ventilated patients: (1) with normal lung function; (2) ARDS). We used the 50 ms scan mode of the EBCT. The beam was positioned 1 cm above the diaphragm. The table position remained unchanged. An electronic trigger was developed, that utilizes the respirators synchronizing signal to start the EBCT at the onset of expiration. During controlled mechanical expiration at two levels of PEEP (0 and 15 cm H2O), pulmonary aeration was rated as: well-aerated (-900HU/-500HU), poorly- aerated (-500HU/-100HU) and non-aerated (-100HU/+100HU). Pathological and normal lung function showed different dynamic changes (FIG.4-12). The different PEEP levels resulted in a significant change of pulmonary aeration in the same patient. Although we studied only a very limited number of patients, respirator triggered EBCT may be accurate in discriminating pathological changes due to the abnormal lung function in the mechanically ventilated patient.

FINE PORE DIFFUSER SYSTEM EVALUATION FOR THE GREEN BAY METROPOLITAN SEWERAGE DISTRICT

EPA Science Inventory

The Green Bay Metropolitan Sewerage District retrofitted two quadrants of their activated sludge aeration system with ceramic and membrane fine pore diffusers to provide savings in energy usage compared to the sparged turbine aerators originally installed. Because significant di...

40 CFR 63.361 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES Ethylene Oxide Emissions Standards... used to facilitate off-gassing of ethylene oxide at a sterilization facility. Aeration room vent means the point(s) through which the evacuation of ethylene oxide-laden air from an aeration room occurs...

German version, inter- and intrarater reliability and internal consistency of the "Agitated Behavior Scale" (ABS-G) in patients with moderate to severe traumatic brain injury.

PubMed

Hellweg, Stephanie; Schuster-Amft, Corina

2016-07-19

Agitation is frequently observed during early recovery after traumatic brain injury (TBI). Agitated behaviour often interferes with a goal-orientated rehabilitation and can be a substantial hindrance to therapy. Despite the relatively high occurance of agitation in TBI population there is no objective assessement in German (G) available. An existing scale with excellent psychometric properties is the "Agitated Behavior Scale (ABS)" developed by Corrigan in 1989. The aim of the study was to translate the Agitated Behavior Scale (ABS) into German (ABS-G) and investigate the inter- and intrarater reliability and internal consistency in patients with moderate to severe TBI. A formal nine-step translation and cross-cultural adaptation procedure (TCCA) was applied. Subsequently a prospective observational patient study was conducted. To examine the interrater reliability and internal consistency, two therapists rated 20 patients independently after a therapy session. This procedure was repeated twice on a weekly basis. The intrarater reliability was assessed through video recordings from three patients. Nine raters scored the demonstrated behaviour on the videotape with the ABS-G independently twice within one month. The inter- and intrarater reliability were evaluated with the Spearman rank correlation coefficient and the quadratic weighted kappa. The internal consistency was tested with Cronbach's alpha. Behaviour of 20 patients (18 males; mean age 41 ± 20.7; mean Functional Independence Measure (FIM) cognitive score on admission 7.1 ± 4.04; mean ABS-G score at first observation 17.3 ± 2.83) was assessed threefold. Interrater reliability yielded a correlation coefficient for ABS-G total score of all 60 paired observations of r s 0.845 and a weighted Kappa of 0.738. Intrarater reliability for ABS-G total score ranged between r s 0.719 and 0.953 and showed a weighted Kappa between 0.871 and 0.953. Cronbach's alpha indicated moderate internal consistency with 0.661. This study demonstrates that the ABS-G is a reliable instrument for evaluating agitation in patients with moderate to severe TBI. Hereby it would be possible to monitor agitation objectively and optimise the management of agitated patients according to international recommendations.

Amelioration of lesions associated with 24-hour suboptimal platelet storage at 16 °C by a p38MAPK inhibitor, VX-702.

PubMed

Wagner, S J; Skripchenko, A; Seetharaman, S; Kurtz, J

2015-04-01

Previous studies with p38MAPK inhibitors at room temperature demonstrated that they improve a large number of platelet storage parameters, but cannot substantially inhibit p38MAPK activation nor protect against widespread decrements in platelet quality parameters during 4 °C storage. In this study, platelet quality parameters and inhibition of p38MAPK by VX-702 were studied after incubation of platelets at 16 °C without agitation, suboptimal storage conditions which produce moderate platelet decrements. Trima apheresis units were collected and aliquoted into three 60-ml CLX storage bags: (i) a control aliquot which was held at 20-24 °C with constant agitation; (ii) a test aliquot which was held at 20-24 °C with agitation until Day 2, when it was reincubated at 16 ± 1 °C for 24 ± 0·5 h without agitation and then returned 20-24 °C with agitation; (iii) a test aliquot containing 1 μm VX-702 stored in an identical fashion as aliquot 2. Aliquots were tested for an array of platelet storage parameters and p38MAPK activation on Days 1, 4 and 7. Many platelet storage parameters and p38MAPK activation were adversely affected by 24-h incubation at 16 °C without agitation. With the exception of ESC, addition of VX-702 prevented p38MAPK activation and the decrements in most observed parameters. Unlike 4 °C storage, VX-702 prevents activation of p38MAPK and decrements in many platelet storage parameters after exposure to 16 °C without agitation for 24 h. © 2014 International Society of Blood Transfusion.

Effect of agitation on methanogenesis stage of two-stage anaerobic digestion of palm oil mill effluent (POME) into biogas

NASA Astrophysics Data System (ADS)

Trisakti, Bambang; Irvan, Zahara, Intan; Taslim, Turmuzi, Muhammad

2017-05-01

This study is an assessment of the effect of agitation on biogas production on methanogenesis stage. Methanogenesis is the second stage of two-stage anaerobic digestion of palm oil effluent (POME) into biogas. The purpose of this study is to get the effect of agitation on growth of microorganisms, degradation of organic substances, and biogas production and composition. Initially, the suitable loading up was determined by varying the HRT at 100, 40, 6, and 4 days in the continuous stirred tank reactor (CSTR) with agitation rate 100 rpm, pH 6.7-7.5, at room temperature. Next, effect of agitation on the process was determined by varying agitation rate at 50, 100, 150, and 200 rpm. The substrate used was the effluent of the acidogenesis stage that fed to the CSTR four times a day. Analysis of total solids (TS), volatile solids (VS), total suspended solids (TSS), volatile suspended solids (VSS), and chemical oxygen demand (COD) were conducted in order to study the growth of microorganisms and their abilities in converting organic compound to produce biogas. Production and composition of biogas were also determined by measuring the volume of biogas and content of H2S and CO2. The result showed that the pH and alkalinity it was still within the range of methanogenesis process. The growth of microorganisms were increased with the increasing of agitation rate. However, the best degradation of organic substances, biogas production, and biogas composition were achieved at 100 rpm. The VS decomposition, COD removal, biogas production, CO2 content, and CH4 content at 100 rpm were 67.44 ± 3.59%, 81.00%, 58.87 ± 6.27 L/kg-ΔVS, 23.36%, and 76.64%, respectively.

Animal-assisted therapy and agitation and depression in nursing home residents with dementia: a matched case-control trial.

PubMed

Majić, Tomislav; Gutzmann, Hans; Heinz, Andreas; Lang, Undine E; Rapp, Michael A

2013-11-01

To investigate the efficacy of animal-assisted therapy (AAT) on symptoms of agitation/aggression and depression in nursing home residents with dementia in a randomized controlled trial. Previous studies have indicated that AAT has beneficial effects on neuropsychiatric symptoms in various psychiatric disorders but few studies have investigated the efficacy of AAT in patients suffering from dementia. Of 65 nursing home residents with dementia (mean [standard deviation] age: 81.8 [9.2] years; mean Mini-Mental State Examination score: 7.1 [0.7]), 27 matched pairs (N = 54) were randomly assigned to either treatment as usual or treatment as usual combined with AAT, administered over 10 weekly sessions. Blinded raters assessed cognitive impairment with the Mini-Mental State Examination, presence of agitation/aggression with the Cohen-Mansfield Agitation Inventory, and depression with the Dementia Mood Assessment Scale at baseline and during a period of 4 weeks after AAT intervention. In the control group, symptoms of agitation/aggression and depression significantly increased over 10 weeks; in the intervention group, patients receiving combined treatment displayed constant frequency and severity of symptoms of agitation/aggression (F1,48 = 6.43; p <0.05) and depression (F1,48 = 26.54; p <0.001). Symptom amelioration did not occur in either group. AAT is a promising option for the treatment of agitation/aggression and depression in patients with dementia. Our results suggest that AAT may delay progression of neuropsychiatric symptoms in demented nursing home residents. Further research is needed to determine its long-time effects. Copyright © 2013 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Tissue dissolution by sodium hypochlorite: effect of concentration, temperature, agitation, and surfactant.

PubMed

Stojicic, Sonja; Zivkovic, Slavoljub; Qian, Wei; Zhang, Hui; Haapasalo, Markus

2010-09-01

Sodium hypochlorite is the most commonly used endodontic irrigant because of its antimicrobial and tissue-dissolving activity. The aim of this study was to evaluate and compare the effects of concentration, temperature, and agitation on the tissue-dissolving ability of sodium hypochlorite. In addition, a hypochlorite product with added surface active agent was compared with conventional hypochlorite solutions. Three sodium hypochlorite solutions from two different manufacturers in concentrations of 1%, 2%, 4%, and 5.8% were tested at room temperature, 37 degrees C, and 45 degrees C with and without agitation by ultrasonic and sonic energy and pipetting. Distilled and sterilized tap water was used as controls. Pieces of bovine muscle tissue (68 +/- 3 mg) were placed in 10 mL of each solution for five minutes. In selected samples, agitation was performed for one, two, or four 15-second periods per each minute. The tissue specimens were weighed before and after treatment, and the percentage of weight loss was calculated. The contact angle on dentin of the three solutions at concentrations of 1% and 5.8% was measured. Weight loss (dissolution) of the tissue increased almost linearly with the concentration of sodium hypochlorite. Higher temperatures and agitation considerably enhanced the efficacy of sodium hypochlorite. The effect of agitation on tissue dissolution was greater than that of temperature; continuous agitation resulted in the fastest tissue dissolution. Hypochlorite with added surface active agent had the lowest contact angle on dentin and was most effective in tissue dissolution in all experimental situations. Optimizing the concentration, temperature, flow, and surface tension can improve the tissue-dissolving effectiveness of hypochlorite even 50-fold. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Relationship between speaking English as a second language and agitation in people with dementia living in care homes: Results from the MARQUE (Managing Agitation and Raising Quality of life) English national care home survey

PubMed Central

Rapaport, P.; Robertson, S.; Marston, L.; Barber, J.; Manela, M.; Livingston, G.

2017-01-01

Objective As not speaking English as a first language may lead to increased difficulties in communication with staff and other residents, we (1) tested our primary hypotheses that care home residents with dementia speaking English as a second language experience more agitation and overall neuropsychiatric symptoms, and (2) explored qualitatively how staff consider that residents' language, ethnicity, and culture might impact on how they manage agitation. Methods We interviewed staff, residents with dementia, and their family carers from 86 care homes (2014–2015) about resident's neuropsychiatric symptoms, agitation, life quality, and dementia severity. We qualitatively interviewed 25 staff. Results Seventy‐one out of 1420 (5%) of care home residents with dementia interviewed spoke English as a second language. After controlling for dementia severity, age, and sex, and accounting for care home and staff proxy clustering, speaking English as a second language compared with as a first language was associated with significantly higher Cohen‐Mansfield Agitation Inventory (adjusted difference in means 8.3, 95% confidence interval 4.1 to 12.5) and Neuropsychiatric inventory scores (4.1, 0.65 to 7.5). Staff narratives described how linguistic and culturally isolating being in a care home where no residents or staff share your culture or language could be for people with dementia, and how this sometimes caused or worsened agitation. Conclusions Considering a person with dementia's need to be understood when selecting a care home and developing technology resources to enable dementia‐friendly translation services could be important strategies for reducing distress of people with dementia from minority ethnic groups who live in care homes. PMID:28971511

Relationship between speaking English as a second language and agitation in people with dementia living in care homes: Results from the MARQUE (Managing Agitation and Raising Quality of life) English national care home survey.

PubMed

Cooper, C; Rapaport, P; Robertson, S; Marston, L; Barber, J; Manela, M; Livingston, G

2018-03-01

As not speaking English as a first language may lead to increased difficulties in communication with staff and other residents, we (1) tested our primary hypotheses that care home residents with dementia speaking English as a second language experience more agitation and overall neuropsychiatric symptoms, and (2) explored qualitatively how staff consider that residents' language, ethnicity, and culture might impact on how they manage agitation. We interviewed staff, residents with dementia, and their family carers from 86 care homes (2014-2015) about resident's neuropsychiatric symptoms, agitation, life quality, and dementia severity. We qualitatively interviewed 25 staff. Seventy-one out of 1420 (5%) of care home residents with dementia interviewed spoke English as a second language. After controlling for dementia severity, age, and sex, and accounting for care home and staff proxy clustering, speaking English as a second language compared with as a first language was associated with significantly higher Cohen-Mansfield Agitation Inventory (adjusted difference in means 8.3, 95% confidence interval 4.1 to 12.5) and Neuropsychiatric inventory scores (4.1, 0.65 to 7.5). Staff narratives described how linguistic and culturally isolating being in a care home where no residents or staff share your culture or language could be for people with dementia, and how this sometimes caused or worsened agitation. Considering a person with dementia's need to be understood when selecting a care home and developing technology resources to enable dementia-friendly translation services could be important strategies for reducing distress of people with dementia from minority ethnic groups who live in care homes. © 2017 The Authors. International Journal of Geriatric Psychiatry Published by John Wiley & Sons Ltd.

Irritable temperament and lifetime psychotic symptoms as predictors of anxiety symptoms in bipolar disorder.

PubMed

Serafini, Gianluca; Geoffroy, Pierre A; Aguglia, Andrea; Adavastro, Giulia; Canepa, Giovanna; Pompili, Maurizio; Amore, Mario

2018-01-01

Affective temperaments, hopelessness, alexithymia, and anxiety/agitation symptoms may play a significant role in the psychopathological characteristics of bipolar disorder (BD). Here, we aimed to investigate the eventual association between the mentioned explanatory variables and anxiety/agitation symptoms in BD. We recruited at the Section of Psychiatry, Department of Neuroscience, University of Genoa (Italy), 92 BD inpatients having a mean age of 52 (±13.8) years. Participants were assessed using specific psychometric instruments. Anxiety/agitation symptoms have been evaluated using the 11-item of the Beck Depression Inventory II (BDI-II). Overall, 53.8% of participants presented with anxiety/agitation symptoms and 46.2% without. The two groups significantly differed about socio-economic status, lifetime psychotic symptoms, and residual depressive symptoms between episodes. Anxiety/agitation symptoms significantly correlated with irritable affective temperament (r = 0.407; p = .01), hopelessness (r = 0.541; p ≤ .001), difficulty identifying feelings (r = 0.440; p ≤ .001), difficulty describing feelings (r = 0.437; p ≤ .001), and externally oriented-thinking (r = 0.393; p ≤ .001). After multivariate analyses, irritable affective temperament (OR = 2.457, p ≤ .01) and less lifetime psychotic symptoms (OR = 0.007, p ≤ .05) remained the only significant variables associated with anxiety/agitation symptoms. The generalization of the main findings is limited by the small sample size and cross-sectional study design. Nevertheless, our results suggest that the careful assessment of affective temperaments and psychotic symptoms may help to early identify BD patients suffering from anxiety/agitation symptoms and may allow to perform targeted interventions in the clinical practice.

The Role of Inhaled Loxapine in the Treatment of Acute Agitation in Patients with Psychiatric Disorders: A Clinical Review.

PubMed

de Berardis, Domenico; Fornaro, Michele; Orsolini, Laura; Iasevoli, Felice; Tomasetti, Carmine; de Bartolomeis, Andrea; Serroni, Nicola; Valchera, Alessandro; Carano, Alessandro; Vellante, Federica; Marini, Stefano; Piersanti, Monica; Perna, Giampaolo; Martinotti, Giovanni; Di Giannantonio, Massimo

2017-02-08

Loxapine is a first generation antipsychotic, belonging to the dibenzoxazepine class. Recently, loxapine has been reformulated at a lower dose, producing an inhaled powder that can be directly administered to the lungs to treat the agitation associated with psychiatric disorders, such as schizophrenia and bipolar disorder. Thus, the aim of this narrative and clinical mini-review was to evaluate the efficacy and tolerability of inhaled loxapine in the treatment of acute agitation in patients with psychiatric disorders. The efficacy of inhaled loxapine has been evaluated in one Phase II trial on patients with schizophrenia, and in two Phase III trials in patients with schizophrenia and bipolar disorder. Moreover, there are two published case series on patients with borderline personality disorder and dual diagnosis patients. Inhaled loxapine has proven to be effective and generally well tolerated when administered to agitated patients with schizophrenia and bipolar disorder. Two case series have suggested that inhaled loxapine may also be useful to treat agitation in patients with borderline personality disorder and with dual diagnosis, but further studies are needed to clarify this point. However, the administration of inhaled loxapine requires at least some kind of patient collaboration, and is not recommended in the treatment of severe agitation in totally uncooperative patients. Moreover, the drug-related risk of bronchospasm must always be kept in mind when planning to use inhaled loxapine, leading to a careful patient assessment prior to, and after, administration. Also, the higher costs of inhaled loxapine, when compared to oral and intramuscular medications, should be taken into account when selecting it for the treatment of agitation.

A controlled trial of aromatherapy for agitation in nursing home patients with dementia.

PubMed

Snow, Lynn A; Hovanec, Linda; Brandt, Jason

2004-06-01

Two controlled trials of aromatherapy to decrease agitation in persons with dementia have recently produced promising results. However, both studies combined the use of essential oils with massage. Thus, it is unclear if the effect of the aromatherapy intervention was the result of smelling or the cutaneous absorption of the oils. The purpose of this study was to determine whether smelling lavender oil decreases the frequency of agitated behaviors in patients with dementia. The study design was within-subjects ABCBA (A = lavender oil, B = thyme oil, C = unscented grapeseed oil): 4 weeks of baseline measurement, 2 weeks for each of the five treatment conditions (10-week total intervention time), and 2 weeks of postintervention measurement. Oil was placed every 3 hours on an absorbent fabric sachet pinned near the collarbone of each participant's shirt. A long-term care facility specifically for persons with dementia. Seven agitated nursing home residents with advanced dementia. Agitation was assessed every 2 days using a modified Cohen-Mansfield Agitation Inventory. Olfactory functioning was assessed with structured olfactory identification and discrimination tasks, and with qualitative behavioral observation during those tasks. Split-middle analyses conducted separately for each patient revealed no treatment effects specific to lavender, no treatment effects nonspecific to pleasant smelling substances, and no treatment effects dependent on order of treatment administration. There were no differences between participants with more and less intact olfactory abilities. There is significant evidence in the neurologic and neuropsychologic literature that persons with dementia have impaired olfactory abilities. Concordant with this literature, this study found no support for the use of a purely olfactory form of aromatherapy to decrease agitation in severely demented patients. Cutaneous application of the essential oil may be necessary to achieve the effects reported in previous controlled studies. Copyright Mary Ann Liebert, Inc.

A prospective study of ketamine versus haloperidol for severe prehospital agitation.

PubMed

Cole, Jon B; Moore, Johanna C; Nystrom, Paul C; Orozco, Benjamin S; Stellpflug, Samuel J; Kornas, Rebecca L; Fryza, Brandon J; Steinberg, Lila W; O'Brien-Lambert, Alex; Bache-Wiig, Peter; Engebretsen, Kristin M; Ho, Jeffrey D

2016-08-01

Ketamine is an emerging drug for the treatment of acute undifferentiated agitation in the prehospital environment, however no prospective comparative studies have evaluated its effectiveness or safety in this clinical setting. We hypothesized 5 mg/kg of intramuscular ketamine would be superior to 10 mg of intramuscular haloperidol for severe prehospital agitation, with time to adequate sedation as the primary outcome measure. This was a prospective open label study of all patients in an urban EMS system requiring chemical sedation for severe acute undifferentiated agitation that were subsequently transported to the EMS system's primary Emergency Department. All paramedics were trained in the Altered Mental Status Scale and prospectively recorded agitation scores on all patients. Two 6-month periods where either ketamine or haloperidol was the first-line therapy for severe agitation were prospectively compared primarily for time to adequate sedation. Secondary outcomes included laboratory data and adverse medication events. 146 subjects were enrolled; 64 received ketamine, 82 received haloperidol. Median time to adequate sedation for the ketamine group was 5 minutes (range 0.4-23) vs. 17 minutes (range 2-84) in the haloperidol group (difference 12 minutes, 95% CI 9-15). Complications occurred in 49% (27/55) of patients receiving ketamine vs. 5% (4/82) in the haloperidol group. Complications specific to the ketamine group included hypersalivation (21/56, 38%), emergence reaction (5/52, 10%), vomiting (5/57, 9%), and laryngospasm (3/55, 5%). Intubation was also significantly higher in the ketamine group; 39% of patients receiving ketamine were intubated vs. 4% of patients receiving haloperidol. Ketamine is superior to haloperidol in terms of time to adequate sedation for severe prehospital acute undifferentiated agitation, but is associated with more complications and a higher intubation rate.

Intramuscular olanzapine versus intramuscular haloperidol plus lorazepam for the treatment of acute schizophrenia with agitation: An open-label, randomized controlled trial.

PubMed

Huang, Charles Lung-Cheng; Hwang, Tzung-Jeng; Chen, Yi-Hsing; Huang, Guan-Hua; Hsieh, Ming H; Chen, Hsiu-Hsi; Hwu, Hai-Gwo

2015-05-01

To compare the efficacy and safety profile between intramuscular (IM) olanzapine and IM haloperidol plus IM lorazepam in acute schizophrenic patients with moderate to severe agitation. This was a prospective, randomized, open-label study. Acutely agitated patients with schizophrenia or schizoaffective disorder (n = 67) were randomized to receive 10 mg IM olanzapine (n = 37) or 5 mg IM haloperidol plus 2 mg IM lorazepam (n = 30). Agitation was measured with Positive and Negative Syndrome Scale Excited Component (PANSS-EC) and Agitation-Calmness Evaluation Scale (ACES) during the first 2 hours and at 24 hours after the first injection. Safety was assessed using the Simpson-Angus Scale and Barnes Akathisia Rating Scale and by recording adverse events at 24 hours following the first injection. The Clinical Global Impression-Severity scale was also rated. The PANSS-EC scores decreased significantly at 2 hours after the first injection in both groups (olanzapine: -10.2, p < 0.001; haloperidol + lorazepam: -9.9, p < 0.001). Haloperidol plus lorazepam was not inferior to olanzapine in reducing agitation at 2 hours. There were no significant differences in PANSS-EC or ACES scores between the two groups within 2 hours following the first injection. The frequencies of adverse events and changes in Clinical Global Impression-Severity, Simpson-Angus Scale, and Barnes Akathisia Rating Scale scores from baseline to 24 hours showed no significant differences between the groups. The findings suggest that IM haloperidol (5 mg) plus lorazepam (2 mg) is not inferior to IM olanzapine (10 mg) in the treatment of acute schizophrenic patients with moderate to severe agitation (ClinialTrials.gov identifier number NCT00797277). Copyright © 2015. Published by Elsevier B.V.

Complementary medicine for treatment of agitation and delirium in older persons: a systematic review and narrative synthesis.

PubMed

Levy, Ilana; Attias, Samuel; Ben-Arye, Eran; Bloch, Boaz; Schiff, Elad

2017-05-01

Agitation and delirium frequently occur in cognitively impaired older people. We conducted a systematic review with narrative synthesis of the literature aiming to assess effectiveness of complementary and alternative medicine (CAM) modalities to address these conditions. Following preliminary search, we included 40 original researches on CAM treatment of delirium and agitation in older persons. Then, the quality of these studies was assessed using the Downs and Black Checklist and Quality Assessment Tool for Studies with Diverse Designs, and the effect sizes were calculated. We subsequently conducted a narrative synthesis of the main findings, including theory development, preliminary synthesis, exploration of relationships within and between studies, and assessment of synthesis robustness. Forty articles that met the inclusion criteria were analyzed. Sixteen of these were randomized controlled trials. One article specifically addressed CAM treatment of delirium in patients without dementia, and the remaining 39 articles described treatments of agitated older persons with dementia. Thirty-five of the 40 included studies suggested that the investigated CAM therapies may ameliorate the severity of agitation and delirium. The physiological surrogates of agitation assessed in these studies included cortisol level, chromogranin A level, and heart rate variability. Very few of the studies systematically assessed safety issues, although no major adverse effects were reported. Overall, the systematic review of the literature suggests that several CAM modalities are potentially beneficial in the treatment of agitation and delirium among older persons. We suggest that promising CAM modalities should be further explored through large-scale randomized controlled trials in different clinical settings. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Electroless deposition of nickel-boron coatings using low frequency ultrasonic agitation: Effect of ultrasonic frequency on the coatings.

PubMed

Bonin, L; Bains, N; Vitry, V; Cobley, A J

2017-05-01

The effect of ultrasound on the properties of Nickel-Boron (NiB) coatings was investigated. NiB coatings were fabricated by electroless deposition using either ultrasonic or mechanical agitation. The deposition of Ni occurred in an aqueous bath containing a reducible metal salt (nickel chloride), reducing agent (sodium borohydride), complexing agent (ethylenediamine) and stabilizer (lead tungstate). Due to the instability of the borohydride in acidic, neutral and slightly alkaline media, pH was controlled at pH 12±1 in order to avoid destabilizing the bath. Deposition was performed in three different configurations: one with a classical mechanical agitation at 300rpm and the other two employing ultrasound at a frequency of either 20 or 35kHz. The microstructures of the electroless coatings were characterized by a combination of optical Microscopy and Scanning Electron Microscope (SEM). The chemistry of the coatings was determined by ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectrometry) after dissolution in aqua regia. The mechanical properties of the coatings were established by a combination of roughness measurements, Vickers microhardness and pin-on-disk tribology tests. Lastly, the corrosion properties were analysed by potentiodynamic polarization. The results showed that low frequency ultrasonic agitation could be used to produce coatings from an alkaline NiB bath and that the thickness of coatings obtained could be increased by over 50% compared to those produced using mechanical agitation. Although ultrasonic agitation produced a smoother coating and some alteration of the deposit morphology was observed, the mechanical and corrosion properties were very similar to those found when using mechanical agitation. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of music therapy compared with general recreational activities in reducing agitation in people with dementia: a randomised controlled trial.

PubMed

Vink, A C; Zuidersma, M; Boersma, F; de Jonge, P; Zuidema, S U; Slaets, J P J

2013-10-01

This study aimed to compare the effects of music therapy with general recreational day activities in reducing agitation in people with dementia, residing in nursing home facilities. In a randomised controlled design, residents with dementia (n = 94) were allocated to either music therapy or recreational activities. Both music therapy and general activities were offered twice weekly for 4 months. Changes in agitation were measured with a modified Cohen-Mansfield Agitation Inventory (CMAI) at four intervals on each intervention day. A mixed model analysis was used to evaluate the effectiveness of music therapy, compared with general activities, on CMAI scores at 4 h after the intervention, controlled for CMAI scores at 1 h before the session and session number. Data were analysed for 77 residents (43 randomised to music therapy and 34 to general activities). In both groups, the intervention resulted in a decrease in agitated behaviours from 1 h before to 4 h after each session. This decrease was somewhat greater in the music therapy group than in the general activities group, but this difference was statistically not significant (F = 2.885, p = 0.090) and disappeared completely after adjustment for Global Deterioration Scale stage (F = 1.500; p = 0.222). Both music therapy and recreational activities lead to a short-term decrease in agitation, but there was no additional beneficial effect of music therapy over general activities. More research is required to provide insight in the effects of music therapy in reducing agitation in demented older people. Copyright © 2012 John Wiley & Sons, Ltd.

Time to Response to Citalopram Treatment for Agitation in Alzheimer Disease.

PubMed

Weintraub, Daniel; Drye, Lea T; Porsteinsson, Anton P; Rosenberg, Paul B; Pollock, Bruce G; Devanand, Devangere P; Frangakis, Constantine; Ismail, Zahinoor; Marano, Christopher; Meinert, Curtis L; Mintzer, Jacobo E; Munro, Cynthia A; Pelton, Gregory; Rabins, Peter V; Schneider, Lon S; Shade, David M; Yesavage, Jerome; Lyketsos, Constantine G

2015-11-01

Agitation is a common and significant problem in Alzheimer disease (AD). In the recent Citalopram for Agitation in Alzheimer's Disease (CitAD) study, citalopram was efficacious for the treatment of AD agitation. Here we examined the time course and predictors of response to treatment. Response in CitAD was defined as a modified Alzheimer Disease Cooperative Study Clinical Global Impression of Change (CGIC) score of 1 or 2 or a Neurobehavioral Rating Scale agitation subscale (NBRS-A) score reduction ≥ 50% from baseline. "Stable early response" was defined as meeting the aforementioned criteria at both weeks 3 and 9, "late response" was response at week 9 but not at week 3, and "unstable response" was response at week 3 but not at week 9. In the primary analyses, citalopram was superior to placebo on both the CGIC and the NBRS-A response measures. Little between-group differences were found in response rates in the first 3 weeks of the study (21% versus 19% on the CGIC). Citalopram patients were more likely than placebo patients to be a late responder (18% versus 8% on CGIC, Fisher's exact p = 0.09; 31% versus 15% on NBRS-A, Fisher's exact p = 0.02). Approximately half of citalopram responders (45%-56%) at end of study achieved response later in the study compared with 30%-44% of placebo responders. Treatment with citalopram for agitation in AD needs to be at least 9 weeks in duration to allow sufficient time for full response. Study duration is an important factor to consider in the design of clinical trials for agitation in AD. Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

Two-Level factorial screening of new plasmid/strain combinations for prodution of recombinant-DNA products.

PubMed

Emborg, C; Jepsen, P K; Biedermann, K

1989-05-01

This article treats the basic problem of selection of experimental conditions for microbiological experiments for evaluation of newly isolated bacterial strains, mutants, or plasmid/strain combinations. For this purpose shake flask experiments in a 2(10-4)confounded factorial design at resolution IV with four blocks of 16 flasks were used. The design was used for testing of two new strain/plasmid combinations (E. coli MT 102/403-SD2 and W 3110/403-SD2) i.e., both strains with the same plasmid 403-SD2. Both strains were integrated in the design, so both strains were tested with nine factors (temperature, aeration, glucose, initial pH, pH regulation, reduced aeration, chloramphenicol, acetate, and glycerol). With both strains the interaction between initial pH and reduced aeration had a significant influence on the yield of the recombinant-DNA product nuclease. There was more than a factor of 10 between lowest and highest yield of product. In this interactive system the strains reacted differently. MT 102/403-SD2 had highest yields at high initial pH (8.4) and no reduction in aeration, whereas W 3110/403-SD2 had highest yields of nuclease at low initial pH (7.4) and reduced aeration (rubber stopper inserted after cultivation for 12 h). These data (and previous work) clearly demonstrate that it is impossible to suggest a simple set of experimental conditions for testing of new plasmid/strain combinations. It is clear that the exclusive application of a standardized growth technique e.g., LB-medium at 37 degrees C at an unspecified and uncontrolled aeration level, may lead to wrong conclusions on properties and potentials of now plasmid/strain combinations and may lead to rejection of useful strains or plasmids.

Spatiotemporal Aeration and Lung Injury Patterns Are Influenced by the First Inflation Strategy at Birth.

PubMed

Tingay, David G; Rajapaksa, Anushi; Zonneveld, C Elroy; Black, Don; Perkins, Elizabeth J; Adler, Andy; Grychtol, Bartłomiej; Lavizzari, Anna; Frerichs, Inéz; Zahra, Valerie A; Davis, Peter G

2016-02-01

Ineffective aeration during the first inflations at birth creates regional aeration and ventilation defects, initiating injurious pathways. This study aimed to compare a sustained first inflation at birth or dynamic end-expiratory supported recruitment during tidal inflations against ventilation without intentional recruitment on gas exchange, lung mechanics, spatiotemporal regional aeration and tidal ventilation, and regional lung injury in preterm lambs. Lambs (127 ± 2 d gestation), instrumented at birth, were ventilated for 60 minutes from birth with either lung-protective positive pressure ventilation (control) or as per control after either an initial 30 seconds of 40 cm H2O sustained inflation (SI) or an initial stepwise end-expiratory pressure recruitment maneuver during tidal inflations (duration 180 s; open lung ventilation [OLV]). At study completion, molecular markers of lung injury were analyzed. The initial use of an OLV maneuver, but not SI, at birth resulted in improved lung compliance, oxygenation, end-expiratory lung volume, and reduced ventilatory needs compared with control, persisting throughout the study. These changes were due to more uniform inter- and intrasubject gravity-dependent spatiotemporal patterns of aeration (measured using electrical impedance tomography). Spatial distribution of tidal ventilation was more stable after either recruitment maneuver. All strategies caused regional lung injury patterns that mirrored associated regional volume states. Irrespective of strategy, spatiotemporal volume loss was consistently associated with up-regulation of early growth response-1 expression. Our results show that mechanical and molecular consequences of lung aeration at birth are not simply related to rapidity of fluid clearance; they are also related to spatiotemporal pressure-volume interactions within the lung during inflation and deflation.

[Effect of Aeration Strategies on Emissions of Nitrogenous Gases and Methane During Sludge Bio-Drying].

PubMed

Qi, Lu; Wei, Yuan-song; Zhang, Jun-ya; Zhao, Chen-yang; Cai, Xing; Zhang, Yuan-li; Shao, Chun-yan; Li, Hong-mei

2016-01-15

The data on nitrogen gas (NH3, N2O, NO) emissions during sludge bio-drying process in China is scarce, especially NO due to its unstable chemical property. In this study, effect of two aeration modes on emissions of methane and nitrogenous gas was compared during the continuous aerated turning pile sludge bio-drying process at full scale. In these two aeration strategies, the one currently used in the plant was set as the control, and the other was set as the test in which the aeration was used for oxygen supply, pile temperature control, and moisture removal in the start-up, middle and final stages, respectively. The results showed that the aeration strategy used in the test could not only obviously accelerate the rate of sludge drying (the moisture contents of the test and the control were 36.6% and 42% on day 11) , but also had a better drying performance (the final moisture contents of the test and the control were 33.6% and 37.6%, respectively) and decreased the ammonia cumulative emission by 5%, (ammonia cumulative emission of the test and the control were 208 mg x m(-3) and 219.8 mg x m(-3), respectively). Though a lower accumulated emission (eCO2) of greenhouse gas in the test at 3.61 kg x t(-1) was observed than that of the control (3.73 kg x t(-1) dry weight) , the cumulative emission of NO in the test at 1.9 g x m(-2) was 15. 9% higher than that of the control (1.6 g x m(-2)).

Control of nitrification/denitrification in an onsite two-chamber intermittently aerated membrane bioreactor with alkalinity and carbon addition: Model and experiment.

PubMed

Perera, Mahamalage Kusumitha; Englehardt, James D; Tchobanoglous, George; Shamskhorzani, Reza

2017-05-15

Denitrifying membrane bioreactors (MBRs) are being found useful in water reuse treatment systems, including net-zero water (nearly closed-loop), non-reverse osmosis-based, direct potable reuse (DPR) systems. In such systems nitrogen may need to be controlled in the MBR to meet the nitrate drinking water standard in the finished water. To achieve efficient nitrification and denitrification, the addition of alkalinity and external carbon may be required, and control of the carbon feed rate is then important. In this work, an onsite, two-chamber aerobic nitrifying/denitrifying MBR, representing one unit process of a net-zero water, non-reverse osmosis-based DPR system, was modeled as a basis for control of the MBR internal recycling rate, aeration rate, and external carbon feed rate. Specifically, a modification of the activated sludge model ASM2dSMP was modified further to represent the rate of recycling between separate aerobic and anoxic chambers, rates of carbon and alkalinity feed, and variable aeration schedule, and was demonstrated versus field data. The optimal aeration pattern for the modeled reactor configuration and influent matrix was found to be 30 min of aeration in a 2 h cycle (104 m 3 air/d per 1 m 3 /d average influent), to ultimately meet the nitrate drinking water standard. Optimal recycling ratios (inter-chamber flow to average daily flow) were found to be 1.5 and 3 during rest and mixing periods, respectively. The model can be used to optimize aeration pattern and recycling ratio in such MBRs, with slight modifications to reflect reactor configuration, influent matrix, and target nitrogen species concentrations, though some recalibration may be required. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aeration optimization through operation at low dissolved oxygen concentrations: Evaluation of oxygen mass transfer dynamics in different activated sludge systems.

PubMed

Fan, Haitao; Qi, Lu; Liu, Guoqiang; Zhang, Yuankai; Fan, Qiang; Wang, Hongchen

2017-05-01

In wastewater treatment plants (WWTPs) using the activated sludge process, two methods are widely used to improve aeration efficiency - use of high-efficiency aeration devices and optimizing the aeration control strategy. Aeration efficiency is closely linked to sludge characteristics (such as concentrations of mixed liquor suspended solids (MLSS) and microbial communities) and operating conditions (such as air flow rate and operational dissolved oxygen (DO) concentrations). Moreover, operational DO is closely linked to effluent quality. This study, which is in reference to WWTP discharge class A Chinese standard effluent criteria, determined the growth kinetics parameters of nitrifiers at different DO levels in small-scale tests. Results showed that the activated sludge system could meet effluent criteria when DO was as low as 0.3mg/L, and that nitrifier communities cultivated under low DO conditions had higher oxygen affinity than those cultivated under high DO conditions, as indicated by the oxygen half-saturation constant and nitrification ability. Based on nitrifier growth kinetics and on the oxygen mass transfer dynamic model (determined using different air flow rate (Q' air ) and mixed liquor volatile suspended solids (MLVSS) values), theoretical analysis indicated limited potential for energy saving by improving aeration diffuser performance when the activated sludge system had low oxygen consumption; however, operating at low DO and low MLVSS could significantly reduce energy consumption. Finally, a control strategy coupling sludge retention time and MLVSS to minimize the DO level was discussed, which is critical to appropriate setting of the oxygen point and to the operation of low DO treatment technology. Copyright © 2016. Published by Elsevier B.V.

Lean Methodology Reduces Inappropriate Use of Antipsychotics for Agitation at a Psychiatric Hospital.

PubMed

Goga, Joshana K; Depaolo, Antonio; Khushalani, Sunil; Walters, J Ken; Roca, Robert; Zisselman, Marc; Borleis, Christopher

2017-01-01

To Evaluate the Effects of Applying Lean Methodology-Improving Quality Increasing Efficiency by Eliminating Waste and Reducing Costs-An Approach To Decrease the Prescribing Frequency of Antipsychotics for The Indication of Agitation. Historically Controlled Study. Bheppard Pratt Health System is the Largest Private Provider of Psychiatric Care in Maryland With a Total Bed Capacity of 300. There Were 4 337 Patient Days From November 1 2012 to October 31 2013 on the Dementia Unit. All Patients Admitted on the Dementia Unit Were 65 Years of Age and Older with a Primary Diagnosis of Dementia. our Multidisciplinary Team Used Lean Methodology to Identify the Root Causes and Interventions Necessary to Reduce Inappropriate Antipsychotic Use. The Primary Outcome Was Rate of Inappropriately Indicating Agitation as the Rationale When Prescribing Antipsychotic Medications. There Was a 90% (P < 0.001) Reduction in Rate Of Antipsychotic Prescribing with an Indication of Agitation. The Lean Methodology Interventions Led To A 90% (P < 0.001) Reduction in the Rate of Antipsychotic Prescribing with an Indication of Agitation and a 10% Rate Reduction in Overall Antipsychotic Prescribing. Key Words: Agitation Alzheimer's Antipsychotics Behavioral and Psychological Symptoms of Dementia Centers For Medicare & Medicaid Services Dementia Root-cause Analysis. BPSD = Behavioral and Psychological Symptoms of Dementia CATIE-AD = Clinical Antipsychotic Trials of Intervention Effectiveness in Alzheimer's Disease EMR = Electronic Medical Records GAO = Government Accountability Office GNCIS = Geriatric Neuropsychiatric Clinical Indicator Scale.

A group music intervention using percussion instruments with familiar music to reduce anxiety and agitation of institutionalized older adults with dementia.

PubMed

Sung, Huei-chuan; Lee, Wen-li; Li, Tzai-li; Watson, Roger

2012-06-01

This experimental study aimed to evaluate the effects of a group music intervention on anxiety and agitation of institutionalized older adults with dementia. A total of 60 participants were randomly assigned to an experimental or a control group. The experimental group received a 30-min music intervention using percussion instruments with familiar music in a group setting in mid afternoon twice weekly for 6 weeks, whereas the control group received usual care with no music intervention. The Rating of Anxiety in Dementia scale was used to assess anxiety, and Cohen-Mansfield Agitation Inventory was used to assess agitation at baseline, week 4 and week 6. Repeated measures analysis of covariance indicated that older adults who received a group music intervention had a significantly lower anxiety score than those in the control group while controlling for pre-test score and cognitive level (F = 8.98, p = 0.004). However, the reduction of agitation between two groups was not significantly different. Anxiety and agitation are common in older adults with dementia and have been reported by caregivers as challenging care problems. An innovative group music intervention using percussion instruments with familiar music as a cost-effective approach has the potential to reduce anxiety and improve psychological well-being of those with dementia. Copyright © 2011 John Wiley & Sons, Ltd.

[Agitation in people with dementia : Scoping review and putting the phenomenon into perspective using the comfort theory and the concept of attachment].

PubMed

Schaub, Corinne; Morin, Diane; von Gunten, Armin

2016-06-01

Agitation in hospitalized demented patients is troublesome and disruptive for both patients and caregivers. The literature indicates that agitation is strongly related to physical or psychological discomfort and its recent definition includes the additional relation to emotional distress. Hospitalization associated with major cognitive difficulties further activates the need for attachment and security to which caregivers must pay attention. This synthesis review first deals with the evidence related to agitation in people with dementia and its relationship with discomfort. A description of the difficulties with which caregivers must cope follows. The need to primarily use nonpharmacological approaches during agitation to meet the underlying needs causing discomfort is then developed. Recommended approaches generally involve a relational contact, even if facing the risk of mobilizing frequently unsecured and anxious attachment patterns in this population. A conceptual positioning supported by the Kolcaba comfort theory will position this knowledge. A particular point of this theory, based on previous experiences of patients, will be analyzed based on attachment characteristics of people with dementia.

Stepped chute training wall height requirements

USDA-ARS?s Scientific Manuscript database

Stepped chutes are commonly used for overtopping protection for embankment dams. Aerated flow is commonly associated with stepped chutes if the chute has sufficient length. The aeration and turbulence of the flow can create a significant amount of splash over the training wall if not appropriately...

[Quick Start-up and Sustaining of Shortcut Nitrification in Continuous Flow Reactor].

PubMed

Wu, Peng; Zhang Shi-ying; Song, Yin-ling; Xu, Yue-zhong; Shen, Yao-liang

2016-04-15

How to achieve fast and stable startup of shortcut nitrification has a very important practical value for treatment of low C/N ratio wastewater. Thus, the quick start-up and sustaining of shortcut nitrification were investigated in continuous flow reactor targeting at the current situation of urban wastewater treatment plant using a continuous flow process. The results showed that quick start-up of shortcut nitrification could be successfully achieved in a continuous flow reactor after 60 days' operation with intermittent aeration and controlling of three stages of stop/aeration time (15 min/45 min, 45 min/45 min and 30 min/30 min). The nitrification rates could reach 90% or 95% respectively, while influent ammonia concentrations were 50 or 100 mg · L⁻¹ with stop/aeration time of 30 min/30 min. In addition, intermittent aeration could inhibit the activity of nitrite oxidizing bacteria (NOB), while short hydraulic retention time (HRT) may wash out NOB. And a combined use of both measures was beneficial to sustain shortcut nitrification.

Improving industrial full-scale production of baker's yeast by optimizing aeration control.

PubMed

Blanco, Carlos A; Rayo, Julia; Giralda, José M

2008-01-01

This work analyzes the control of optimum dissolved oxygen of an industrial fed-batch procedure in which baker's yeast (Saccharomyces cerevisiae) is grown under aerobic conditions. Sugar oxidative metabolism was controlled by monitoring aeration, molasses flows, and yeast concentration in the propagator along the later stage of the propagation, and keeping pH and temperature under controlled conditions. A large number of fed-batch growth experiments were performed in the tank for a period of 16 h, for each of the 3 manufactured commercial products. For optimization and control of cultivations, the growth and metabolite formation were quantified through measurement of specific growth and ethanol concentration. Data were adjusted to a model of multiple lineal regression, and correlations representing dissolved oxygen as a function of aeration, molasses, yeast concentration in the broth, temperature, and pH were obtained. The actual influence of each variable was consistent with the mathematical model, further justified by significant levels of each variable, and optimum aeration profile during the yeast propagation.

Simulation of water removal process and optimization of aeration strategy in sewage sludge composting.

PubMed

Zhou, Hai-Bin; Chen, Tong-Bin; Gao, Ding; Zheng, Guo-Di; Chen, Jun; Pan, Tian-Hao; Liu, Hong-Tao; Gu, Run-Yao

2014-11-01

Reducing moisture in sewage sludge is one of the main goals of sewage sludge composting and biodrying. A mathematical model was used to simulate the performance of water removal under different aeration strategies. Additionally, the correlations between temperature, moisture content (MC), volatile solids (VS), oxygen content (OC), and ambient air temperature and aeration strategies were predicted. The mathematical model was verified based on coefficients of correlation between the measured and predicted results of over 0.80 for OC, MC, and VS, and 0.72 for temperature. The results of the simulation showed that water reduction was enhanced when the average aeration rate (AR) increased to 15.37 m(3) min(-1) (6/34 min/min, AR: 102.46 m(3) min(-1)), above which no further increase was observed. Furthermore, more water was removed under a higher on/off time of 7/33 (min/min, AR: 87.34 m(3) min(-1)), and when ambient air temperature was higher. Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of oxygen in the liquid fermentation of wheat bran.

PubMed

Savolainen, Otto I; Coda, Rossana; Suomi, Katja; Katina, Kati; Juvonen, Riikka; Hanhineva, Kati; Poutanen, Kaisa

2014-06-15

The extensive use of wheat bran as a food ingredient is limited due to its bitter taste and hard texture. To overcome these, some preprocessing methods, such as fermentation with yeast and lactic acid bacteria or enzymatic treatments have been proposed. The current work studied microbial communities, acidification, ethanol formation and metabolite profile of wheat bran fermented in either aerated or anaerobic conditions. In aerated conditions, yeasts grew better and the production of organic acids was smaller, and hence pH was higher. In anaerobic conditions, lactic acid bacteria and endogenous heterotrophic bacteria grew better. Aeration had a large effect on the sourdough metabolite profile, as analyzed by UPLC-qTOF-MS. Anaerobic conditions induced degradation of ferulic and caffeic acids, whereas the amount of sinapic acid increased. Aeration caused degradation of amino acids and hydroxycinnamic acid derivatives of polyamines. The results suggest that the control of oxygen could be used for tailoring the properties of bran sourdough. Copyright © 2013 Elsevier Ltd. All rights reserved.

Petrous apex cholesterol granuloma aeration: does it matter?

PubMed

Castillo, Michael P; Samy, Ravi N; Isaacson, Brandon; Roland, Peter S

2008-04-01

To determine whether aeration of surgically treated petrous apex cholesterol granulomas (PA CG) has any correlation with resolution of symptoms. Retrospective chart review. Twenty-six patients with a petrous apex cholesterol granuloma during a 16-year period were reviewed. Seventeen of 26 (65%) patients underwent surgical intervention. Preoperative symptoms included headache, facial weakness/twitching or numbness, vertigo, hearing loss, vision changes, and tinnitus. Postoperative symptoms resolved in 9 of the 16 patients (56%). Three patients had a postoperative headache. Facial nerve dysfunction persisted or recurred in four patients. One patient was lost to follow-up. Thirteen patients had postoperative imaging. All 13 (100%) patients demonstrated stable or increased size of PA CG with no evidence of aeration. Revision surgery was performed in four patients (25%) for facial nerve symptoms or persistent headaches. The extent of PA CG aeration on postoperative imaging had no correlation to symptom resolution or cyst enlargement. Revision surgery should not depend on imaging alone but primarily on patient symptoms and physical exam.

Pilot scale experiment with MBR operated in intermittent aeration condition: analysis of biological performance.

PubMed

Capodici, M; Di Bella, G; Di Trapani, D; Torregrossa, M

2015-02-01

The effect of intermittent aeration (IA) on a MBR system was investigated. The study was aimed at analyzing different working conditions and the influence of different IA cycles on the biological performance of the MBR pilot plant, in terms of organic carbon and ammonium removal as well as extracellular polymeric substances (EPSs) production. The membrane modules were placed in a separate compartment, continuously aerated. This configuration allowed to disconnect from the filtration stage the biological phenomena occurring into the IA bioreactor. The observed results highlighted good efficiencies, in terms of organic carbon and ammonium removal. It was noticed a significant soluble microbial products (SMPs) release, likely related to the higher metabolic stress that anoxic conditions exerted on the biomass. However, the proposed configuration, with the membranes in a separate compartment, allowed to reduce the EPSs in the membrane tank even during the non-aerated phase, thus lowering fouling development. Copyright © 2014 Elsevier Ltd. All rights reserved.

Aroma profiling of an aerated fermentation of natural grape must with selected yeast strains at pilot scale.

PubMed

Tronchoni, Jordi; Curiel, José Antonio; Sáenz-Navajas, María Pilar; Morales, Pilar; de-la-Fuente-Blanco, Arancha; Fernández-Zurbano, Purificación; Ferreira, Vicente; Gonzalez, Ramon

2018-04-01

The use of non-Saccharomyces strains in aerated conditions has proven effective for alcohol content reduction in wine during lab-scale fermentation. The process has been scaled up to 20 L batches, in order to produce lower alcohol wines amenable to sensory analysis. Sequential instead of simultaneous inoculation was chosen to prevent oxygen exposure of Saccharomyces cerevisiae during fermentation, since previous results indicated that this would result in increased acetic acid production. In addition, an adaptation step was included to facilitate non-Saccharomyces implantation in natural must. Wines elaborated with Torulaspora delbrueckii or Metschnikowia pulcherrima in aerated conditions contained less alcohol than control wine (S. cerevisiae, non-aerated). Sensory and aroma analysis revealed that the quality of mixed fermentations was affected by the high levels of some yeast amino acid related byproducts, which suggests that further progress requires a careful selection of non-Saccharomyces strains and the use of specific N-nutrients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Computational fluid dynamics modelling of hydraulics and sedimentation in process reactors during aeration tank settling.

PubMed

Jensen, M D; Ingildsen, P; Rasmussen, M R; Laursen, J

2006-01-01

Aeration tank settling is a control method allowing settling in the process tank during high hydraulic load. The control method is patented. Aeration tank settling has been applied in several waste water treatment plants using the present design of the process tanks. Some process tank designs have shown to be more effective than others. To improve the design of less effective plants, computational fluid dynamics (CFD) modelling of hydraulics and sedimentation has been applied. This paper discusses the results at one particular plant experiencing problems with partly short-circuiting of the inlet and outlet causing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in the process tank. The model has allowed us to establish a clear picture of the problems arising at the plant during aeration tank settling. Secondly, several process tank design changes have been suggested and tested by means of computational fluid dynamics modelling. The most promising design changes have been found and reported.

Effect of aerated concrete blockwork joints on the heat transfer performance uniformity

NASA Astrophysics Data System (ADS)

Pukhkal, Viktor; Murgul, Vera

2018-03-01

Analysis of data on the effect of joints of the aerated concrete blocks on the heat transfer uniformity of exterior walls was carried out. It was concluded, that the values of the heat transfer performance uniformity factor in the literature sources were obtained for the regular fragment of a wall construction by approximate addition of thermal conductivities. Heat flow patterns for the aerated concrete exterior walls amid different values of the thermal conductivity factors and design ambient air temperature of -26 °C were calculated with the use of "ELCUT" software for modelling of thermal patterns by finite element method. There were defined the values for the heat transfer performance uniformity factor, reduced total thermal resistance and heat-flux density for the exterior walls. The calculated values of the heat transfer performance uniformity factors, as a function of the coefficient of thermal conductivity of aerated concrete blocks, differ from the known data by a more rigorous thermal and physical substantiation.

Recovery of ammonia from swine manure using gas-permeable membranes: effect of aeration.

PubMed

García-González, M C; Vanotti, M B; Szogi, A A

2015-04-01

The gas-permeable membrane process can recover ammonia from manure, reducing pollution whilst converting ammonia into an ammonium salt fertilizer. The process involves manure pH control to increase ammonium (NH4(+)) recovery rate that is normally carried out using an alkali. In this study a new strategy to avoid the use of alkali was tested applying low-rate aeration and nitrification inhibition. The wastewater used was raw swine manure with 2390 mg NH4(+)-N/L. Results showed that aeration increased pH above 8.5 allowing quick transformation of NH4(+) into gaseous ammonia (NH3) and efficient recovery by permeation through the submerged membrane. The overall NH4(+) recovery obtained with aeration was 98% and ammonia emissions losses were less than 1.5%. The new approach can substitute large amounts of alkali chemicals needed to obtain high NH4(+) recovery with important economic and environmental savings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biotreatment of textile effluent in static bioreactor by Curvularia lunata URM 6179 and Phanerochaete chrysosporium URM 6181.

PubMed

Miranda, Rita de Cássia M de; Gomes, Edelvio de Barros; Pereira, Nei; Marin-Morales, Maria Aparecida; Machado, Katia Maria Gomes; Gusmão, Norma Buarque de

2013-08-01

Investigations on biodegradation of textile effluent by filamentous fungi strains Curvularia lunata URM 6179 and Phanerochaete chrysosporium URM 6181 were performed in static bioreactors under aerated and non-aerated conditions. Spectrophotometric, HPLC/UV and LC-MS/MS analysis were performed as for to confirm, respectively, decolourisation, biodegradation and identity of compounds in the effluent. Enzymatic assays revealed higher production of enzymes laccase (Lac), lignin peroxidase (LiP) and manganese-dependent peroxidase (MnP) by P. chrysosporium URM 6181 in aerated bioreactor (2020; 39 and 392 U/l, respectively). Both strains decolourised completely the effluent after ten days and biodegradation of the most predominant indigo dye was superior in aerated bioreactor (96%). Effluent treated by P. chrysosporium URM 6181 accumulated a mutagenic metabolite derived from indigo. The C. lunata URM 6179 strain, showed to be more successful for assure the environmental quality of treated effluent. These systems were found very effective for efficient fungal treatment of textile effluent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effective pine bark composting with the Dome Aeration Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trois, Cristina; Polster, Andreas

2007-07-01

In South Africa garden refuse is primarily disposed of in domestic landfills. Due to the large quantities generated, any form of treatment would be beneficial for volume reduction, waste stabilization and resource recovery. Dome Aeration Technology (DAT) is an advanced process for aerobic biological degradation of garden refuse and general waste [Paar, S., Brummack, J., Gemende, B., 1999a. Advantages of dome aeration in mechanical-biological waste treatment. In: Proceedings of the 7th International Waste Management and Landfill Symposium, Cagliari, 4-8 October 1999; Paar, S., Brummack, J., Gemende, B., 1999b. Mechanical-biological waste stabilization by the dome aeration method. Environment Protection Engineering 25more » (3/99). Mollekopf, N., Brummack, J., Paar, S., Vorster, K., 2002. Use of the Dome Aeration Technology for biochemical stabilization of waste prior to landfilling. In: Proceedings of the Wastecon 2002, Waste Congress and Exhibition, Durban, South Africa.]. It is a non-reactor open windrow composting process, with the main advantage being that the input material needs no periodic turning. A rotting time of only 3-4 months indicates the high efficiency. Additionally, the low capital/operational costs, low energy inputs and limited plant requirements provide potential for use in aerobic refuse stabilization. The innovation in the DAT process is the passive aeration achieved by thermally driven advection through open windrows caused by temperature differences between the degrading material and the outside environment. This paper investigates the application of Dome Aeration Technology to pine bark composting as part of an integrated waste management strategy. A full-scale field experiment was performed at the Bisasar Road Landfill Site in Durban to assess the influence of climate, waste composition and operational conditions on the process. A test windrow was constructed and measurements of temperature and airflow through the material were taken. The process monitoring revealed that prevailing climatic conditions in a subtropical location do not affect the high efficiency of this technology. However, the composition of the input material can be detrimental for production of high quality compost because of a lack of nitrate.« less

Pilot study on arsenic removal from groundwater using a small-scale reverse osmosis system-Towards sustainable drinking water production.

PubMed

Schmidt, Stefan-André; Gukelberger, Ephraim; Hermann, Mario; Fiedler, Florian; Großmann, Benjamin; Hoinkis, Jan; Ghosh, Ashok; Chatterjee, Debashis; Bundschuh, Jochen

2016-11-15

Arsenic contamination of groundwater is posing a serious challenge to drinking water supplies on a global scale. In India and Bangladesh, arsenic has caused the most serious public health issue in the world for nearly two decades. The aim of this work was to study an arsenic removal system based on reverse osmosis at pilot scale treating two different water sources from two different locations in the State of Bihar, India. For this purpose two villages, Bind Toli and Ramnagar in the Patna District were selected, both located very close to the river Ganga. The trials were conducted with aerated and non-aerated groundwater. It is the first time that the arsenic removal efficiency for aerated and non-aerated groundwater by reverse osmosis technology in combination with an energy-saving recovery system have been studied. As the principle of reverse osmosis requires a relatively high pressure, its energy demand is naturally high. By using an energy recovery system, this demand can be lowered, leading to an energy demand per liter permeate of 3-4Wh/L only. Due to high iron levels in the groundwater and as a consequence the precipitation of ferric (hydr)oxides, it was necessary to develop a granular media filter for the trials under aeration in order to protect the membrane from clogging. Two different materials, first locally available sand, and second commercially available anthracite were tested in the granular media filter. For the trials with aerated groundwater, total arsenic removal efficiency at both locations was around 99% and the arsenic concentration in permeate was in compliance with the WHO and National Indian Standard of 10μg/L. However, trials under anoxic conditions with non-aerated groundwater could not comply with this standard. Additionally a possible safe discharge of the reverse osmosis concentrate into an abandoned well was studied. It was observed that re-injection of reject water underground may offer a safe disposal option. However, long-term hydrogeological studies need to be conducted for confirmation. Copyright © 2016 Elsevier B.V. All rights reserved.

A systematic review of the clinical effectiveness and cost-effectiveness of sensory, psychological and behavioural interventions for managing agitation in older adults with dementia.

PubMed

Livingston, Gill; Kelly, Lynsey; Lewis-Holmes, Elanor; Baio, Gianluca; Morris, Stephen; Patel, Nishma; Omar, Rumana Z; Katona, Cornelius; Cooper, Claudia

2014-06-01

Agitation is common, persistent and distressing in dementia and is linked with care breakdown. Psychotropic medication is often ineffective or harmful, but the evidence regarding non-pharmacological interventions is unclear. We systematically reviewed and synthesised the evidence for clinical effectiveness and cost-effectiveness of non-pharmacological interventions for reducing agitation in dementia, considering dementia severity, the setting, the person with whom the intervention is implemented, whether the effects are immediate or longer term, and cost-effectiveness. We searched twice using relevant search terms (9 August 2011 and 12 June 2012) in Web of Knowledge (incorporating MEDLINE); EMBASE; British Nursing Index; the Health Technology Assessment programme database; PsycINFO; NHS Evidence; System for Information on Grey Literature; The Stationery Office Official Documents website; The Stationery National Technical Information Service; Cumulative Index to Nursing and Allied Health Literature; and The Cochrane Library. We also searched Cochrane reviews of interventions for behaviour in dementia, included papers' references, and contacted authors about 'missed' studies. We included quantitative studies, evaluating non-pharmacological interventions for agitation in dementia, in all settings. We rated quality, prioritising higher-quality studies. We separated results by intervention type and agitation level. As we were unable to meta-analyse results except for light therapy, we present a qualitative evidence synthesis. In addition, we calculated standardised effect sizes (SESs) with available data, to compare heterogeneous interventions. In the health economic analysis, we reviewed economic studies, calculated the cost of effective interventions from the effectiveness review, calculated the incremental cost per unit improvement in agitation, used data from a cohort study to evaluate the relationship between health and social care costs and health-related quality of life (DEMQOL-Proxy-U scores) and developed a new cost-effectiveness model. We included 160 out of 1916 papers screened. Supervised person-centred care, communication skills (SES = -1.8 to -0.3) or modified dementia care mapping (DCM) with implementing plans (SES = -1.4 to -0.6) were all efficacious at reducing clinically significant agitation in care home residents, both immediately and up to 6 months afterwards. In care home residents, during interventions but not at follow-up, activities (SES = -0.8 to -0.6) and music therapy (SES = -0.8 to -0.5) by protocol reduced mean levels of agitation; sensory intervention (SES = -1.3 to -0.6) reduced mean and clinically significant symptoms. Advantages were not demonstrated with 'therapeutic touch' or individualised activity. Aromatherapy and light therapy did not show clinical effectiveness. Training family carers in behavioural or cognitive interventions did not decrease severe agitation. The few studies reporting activities of daily living or quality-of-life outcomes found no improvement, even when agitation had improved. We identified two health economic studies. Costs of interventions which significantly impacted on agitation were activities, £80-696; music therapy, £13-27; sensory interventions, £3-527; and training paid caregivers in person-centred care or communication skills with or without behavioural management training and DCM, £31-339. Among the 11 interventions that were evaluated using the Cohen-Mansfield Agitation Inventory (CMAI), the incremental cost per unit reduction in CMAI score ranged from £162 to £3480 for activities, £4 for music therapy, £24 to £143 for sensory interventions, and £6 to £62 for training paid caregivers in person-centred care or communication skills with or without behavioural management training and DCM. Health and social care costs ranged from around £7000 over 3 months in people without clinically significant agitation symptoms to around £15,000 at the most severe agitation levels. There is some evidence that DEMQOL-Proxy-U scores decline with Neuropsychiatric Inventory agitation scores. A multicomponent intervention in participants with mild to moderate dementia had a positive monetary net benefit and a 82.2% probability of being cost-effective at a maximum willingness to pay for a quality-adjusted life-year of £20,000 and a 83.18% probability at a value of £30,000. Although there were some high-quality studies, there were only 33 reasonably sized (> 45 participants) randomised controlled trials, and lack of evidence means that we cannot comment on many interventions' effectiveness. There were no hospital studies and few studies in people's homes. More health economic data are needed. Person-centred care, communication skills and DCM (all with supervision), sensory therapy activities, and structured music therapies reduce agitation in care-home dementia residents. Future interventions should change care home culture through staff training and permanently implement evidence-based treatments and evaluate health economics. There is a need for further work on interventions for agitation in people with dementia living in their own homes. The study was registered as PROSPERO no. CRD42011001370. The National Institute for Health Research Health Technology Assessment programme.

Effect of citalopram on agitation in Alzheimer disease: the CitAD randomized clinical trial.

PubMed

Porsteinsson, Anton P; Drye, Lea T; Pollock, Bruce G; Devanand, D P; Frangakis, Constantine; Ismail, Zahinoor; Marano, Christopher; Meinert, Curtis L; Mintzer, Jacobo E; Munro, Cynthia A; Pelton, Gregory; Rabins, Peter V; Rosenberg, Paul B; Schneider, Lon S; Shade, David M; Weintraub, Daniel; Yesavage, Jerome; Lyketsos, Constantine G

2014-02-19

Agitation is common, persistent, and associated with adverse consequences for patients with Alzheimer disease. Pharmacological treatment options, including antipsychotics are not satisfactory. The primary objective was to evaluate the efficacy of citalopram for agitation in patients with Alzheimer disease. Key secondary objectives examined effects of citalopram on function, caregiver distress, safety, cognitive safety, and tolerability. The Citalopram for Agitation in Alzheimer Disease Study (CitAD) was a randomized, placebo-controlled, double-blind, parallel group trial that enrolled 186 patients with probable Alzheimer disease and clinically significant agitation from 8 academic centers in the United States and Canada from August 2009 to January 2013. Participants (n = 186) were randomized to receive a psychosocial intervention plus either citalopram (n = 94) or placebo (n = 92) for 9 weeks. Dosage began at 10 mg per day with planned titration to 30 mg per day over 3 weeks based on response and tolerability. Primary outcome measures were based on scores from the 18-point Neurobehavioral Rating Scale agitation subscale (NBRS-A) and the modified Alzheimer Disease Cooperative Study-Clinical Global Impression of Change (mADCS-CGIC). Other outcomes were based on scores from the Cohen-Mansfield Agitation Inventory (CMAI) and the Neuropsychiatric Inventory (NPI), ability to complete activities of daily living (ADLs), caregiver distress, cognitive safety (based on scores from the 30-point Mini Mental State Examination [MMSE]), and adverse events. Participants who received citalopram showed significant improvement compared with those who received placebo on both primary outcome measures. The NBRS-A estimated treatment difference at week 9 (citalopram minus placebo) was -0.93 (95% CI, -1.80 to -0.06), P = .04. Results from the mADCS-CGIC showed 40% of citalopram participants having moderate or marked improvement from baseline compared with 26% of placebo recipients, with estimated treatment effect (odds ratio [OR] of being at or better than a given CGIC category) of 2.13 (95% CI, 1.23-3.69), P = .01. Participants who received citalopram showed significant improvement on the CMAI, total NPI, and caregiver distress scores but not on the NPI agitation subscale, ADLs, or in less use of rescue lorazepam. Worsening of cognition (-1.05 points; 95% CI, -1.97 to -0.13; P = .03) and QT interval prolongation (18.1 ms; 95% CI, 6.1-30.1; P = .01) were seen in the citalopram group. Among patients with probable Alzheimer disease and agitation who were receiving psychosocial intervention, the addition of citalopram compared with placebo significantly reduced agitation and caregiver distress; however, cognitive and cardiac adverse effects of citalopram may limit its practical application at the dosage of 30 mg per day. clinicaltrials.gov Identifier: NCT00898807.

Effect of Dextromethorphan-Quinidine on Agitation in Patients With Alzheimer Disease Dementia: A Randomized Clinical Trial.

PubMed

Cummings, Jeffrey L; Lyketsos, Constantine G; Peskind, Elaine R; Porsteinsson, Anton P; Mintzer, Jacobo E; Scharre, Douglas W; De La Gandara, Jose E; Agronin, Marc; Davis, Charles S; Nguyen, Uyen; Shin, Paul; Tariot, Pierre N; Siffert, João

Agitation is common among patients with Alzheimer disease; safe, effective treatments are lacking. To assess the efficacy, safety, and tolerability of dextromethorphan hydrobromide-quinidine sulfate for Alzheimer disease-related agitation. Phase 2 randomized, multicenter, double-blind, placebo-controlled trial using a sequential parallel comparison design with 2 consecutive 5-week treatment stages conducted August 2012-August 2014. Patients with probable Alzheimer disease, clinically significant agitation (Clinical Global Impressions-Severity agitation score ≥4), and a Mini-Mental State Examination score of 8 to 28 participated at 42 US study sites. Stable dosages of antidepressants, antipsychotics, hypnotics, and antidementia medications were allowed. In stage 1, 220 patients were randomized in a 3:4 ratio to receive dextromethorphan-quinidine (n = 93) or placebo (n = 127). In stage 2, patients receiving dextromethorphan-quinidine continued; those receiving placebo were stratified by response and rerandomized in a 1:1 ratio to dextromethorphan-quinidine (n = 59) or placebo (n = 60). The primary end point was change from baseline on the Neuropsychiatric Inventory (NPI) Agitation/Aggression domain (scale range, 0 [absence of symptoms] to 12 [symptoms occur daily and with marked severity]). A total of 194 patients (88.2%) completed the study. With the sequential parallel comparison design, 152 patients received dextromethorphan-quinidine and 127 received placebo during the study. Analysis combining stages 1 (all patients) and 2 (rerandomized placebo nonresponders) showed significantly reduced NPI Agitation/Aggression scores for dextromethorphan-quinidine vs placebo (ordinary least squares z statistic, -3.95; P < .001). In stage 1, mean NPI Agitation/Aggression scores were reduced from 7.1 to 3.8 with dextromethorphan-quinidine and from 7.0 to 5.3 with placebo. Between-group treatment differences were significant in stage 1 (least squares mean, -1.5; 95% CI, -2.3 to -0.7; P<.001). In stage 2, NPI Agitation/Aggression scores were reduced from 5.8 to 3.8 with dextromethorphan-quinidine and from 6.7 to 5.8 with placebo. Between-group treatment differences were also significant in stage 2 (least squares mean, -1.6; 95% CI, -2.9 to -0.3; P=.02). Adverse events included falls (8.6% for dextromethorphan-quinidine vs 3.9% for placebo), diarrhea (5.9% vs 3.1% respectively), and urinary tract infection (5.3% vs 3.9% respectively). Serious adverse events occurred in 7.9% with dextromethorphan-quinidine vs 4.7% with placebo. Dextromethorphan-quinidine was not associated with cognitive impairment, sedation, or clinically significant QTc prolongation. In this preliminary 10-week phase 2 randomized clinical trial of patients with probable Alzheimer disease, combination dextromethorphan-quinidine demonstrated clinically relevant efficacy for agitation and was generally well tolerated. clinicaltrials.gov Identifier: NCT01584440.

Agitation

MedlinePlus

There are many causes of agitation. Some of them are: Alcohol intoxication or withdrawal Allergic reaction Caffeine intoxication Certain forms of heart, lung, liver, or kidney disease Intoxication or withdrawal from drugs of abuse (such as ...

Influence of agitation on the removal of nonylphenol by the white-rot fungi Trametes versicolor and Bjerkandera sp. BOL 13.

PubMed

Soares, Ana; Guieysse, Benoit; Mattiasson, Bo

2006-02-01

Bjerkandera sp. BOL 13 removed 95% of nonylphenol (at 9.7 mg nonylphenol L(-1) day(-1)) from aqueous medium after 5 days of incubation in agitated cultures. This removal rate decreased 2.5-fold in static cultures. By comparison, Trametes versicolor removed nonylphenol at 2.8 mg L(-1) day(-1) under conditions of static incubation, probably due to the action of laccase, but no growth was recorded in the agitated bottles.

Estimated splash and training wall height requirements for stepped chutes applied to embankment dams

USDA-ARS?s Scientific Manuscript database

Aging embankment dams are commonly plagued with insufficient spillway capacity. To provide increased spillway capacity, stepped chutes are frequently applied as an overtopping protection system for embankment dams. Stepped chutes with sufficient length develops aerated flow. The aeration and flow...

OFF-GAS ANALYSIS RESULTS AND FINE PORE RETROFIT INFORMATION FOR GLASTONBURY, CONNECTICUT

EPA Science Inventory

In the summer of 1984, the Glastonbury, Connecticut Water Pollution Control Plant underwent a retrofit from a spiral roll coarse bubble to a spiral roll fine pore aeration system. Only diffuser replacement was performed in the aeration tanks. From November 1985 through Septembe...

Evaluation of ammonia emissions from manure incorporated with different soil aerator configurations

USDA-ARS?s Scientific Manuscript database

The incorporation of swine manure with tillage effectively reduces ammonia emissions and conserves crop available N but is not compatible with no-till and many other conservation tillage programs. Rolling-tine aerators potentially provide a means to enhance manure infiltration with limited disruptio...

EVALUATING THE COSTS OF PACKED-TOWER AERATION AND GAC FOR CONTROLLING SELECTED ORGANICS

EPA Science Inventory

This article focuses on a preliminary cost analysis that compares liquid-phase granular activated carbon (GAC) treatment with packed-tower aeration (PTA) treatment, with and without air emissions control. The sensitivity of cost to design and operating variables is also discussed...

CASE HISTORY OF FINE PORE DIFFUSER RETROFIT AT RIDGEWOOD, NEW JERSEY

EPA Science Inventory

In April 1983, the Ridgewood, New Jersey Wastewater Treatment Plant underwent a retrofit from a coarse bubble to a fine pore aeration system. Also, process modification from contact stabilization to tapered aeration occurred. This report presents a case history of plant and aer...

Field study of nitrous oxide production with in situ aeration in a closed landfill site.

PubMed

Nag, Mitali; Shimaoka, Takayuki; Nakayama, Hirofumi; Komiya, Teppei; Xiaoli, Chai

2016-03-01

Nitrous oxide (N(2)O) has gained considerable attention as a contributor to global warming and depilation of stratospheric ozone layer. Landfill is one of the high emitters of greenhouse gas such as methane and N(2)O during the biodegradation of solid waste. Landfill aeration has been attracted increasing attention worldwide for fast, controlled and sustainable conversion of landfills into a biological stabilized condition, however landfill aeration impel N(2)O emission with ammonia removal. N(2)O originates from the biodegradation, or the combustion of nitrogen-containing solid waste during the microbial process of nitrification and denitrification. During these two processes, formation of N(2)O as a by-product from nitrification, or as an intermediate product of denitrification. In this study, air was injected into a closed landfill site and investigated the major N(2)O production factors and correlations established between them. The in-situ aeration experiment was carried out by three sets of gas collection pipes along with temperature probes were installed at three different distances of one, two and three meter away from the aeration point; named points A-C, respectively. Each set of pipes consisted of three different pipes at three different depths of 0.0, 0.75 and 1.5 m from the bottom of the cover soil. Landfill gases composition was monitored weekly and gas samples were collected for analysis of nitrous oxide concentrations. It was evaluated that temperatures within the range of 30-40°C with high oxygen content led to higher generation of nitrous oxide with high aeration rate. Lower O(2) content can infuse N(2)O production during nitrification and high O(2) inhibit denitrification which would affect N(2)O production. The findings provide insights concerning the production potentials of N(2)O in an aerated landfill that may help to minimize with appropriate control of the operational parameters and biological reactions of N turnover. Investigation of nitrous oxide production potential during in situ aeration in an old landfill site revealed that increased temperatures and oxygen content inside the landfill site are potential factors for nitrous oxide production. Temperatures within the range of optimum nitrification process (30-40°C) induce nitrous oxide formation with high oxygen concentration as a by-product of nitrogen turnover. Decrease of oxygen content during nitrification leads increase of nitrous oxide production, while temperatures above 40°C with moderate and/or low oxygen content inhibit nitrous oxide generation.

Incorporation of air into a snack food reduces energy intake

PubMed Central

Osterholt, Kathrin M.; Roe, Liane S.

2007-01-01

This study investigated how the air content of a familiar snack food affected energy intake and whether varying the method of serving the snack modified intake. We tested two versions of an extruded snack (cheese puffs) that were equal in energy density (5.7 kcal/g), but differed in energy per volume (less-aerated snack: 1.00 kcal/ml; more- aerated snack: 0.45 kcal/ml). In a within-subjects design, 16 women and 12 men consumed the snacks ad libitum in the laboratory during four afternoon sessions. A standard volume (1250 ml) of each snack was served once in a bowl and once in an opaque bag. Results showed that intake of the two snacks differed significantly by energy (p=0.0003) and volume (p<0.0001); subjects consumed 21% less weight and energy (70±17 kcal) of the more-aerated snack than the less-aerated snack, although they consumed a 73% greater volume of the more-aerated snack (239±24 ml). These findings suggest that subjects responded to both the weight and volume of the snack. Despite differences in intake, hunger and fullness ratings did not differ across conditions. The serving method did not significantly affect intake. Results from this study indicate that incorporating air into food provides a strategy to reduce energy intake from energy-dense snacks. PMID:17188782

Minimizing N2O emissions and carbon footprint on a full-scale activated sludge sequencing batch reactor.

PubMed

Rodriguez-Caballero, A; Aymerich, I; Marques, Ricardo; Poch, M; Pijuan, M

2015-03-15

A continuous, on-line quantification of the nitrous oxide (N2O) emissions from a full-scale sequencing batch reactor (SBR) placed in a municipal wastewater treatment plant (WWTP) was performed in this study. In general, N2O emissions from the biological wastewater treatment system were 97.1 ± 6.9 g N2O-N/Kg [Formula: see text] consumed or 6.8% of the influent [Formula: see text] load. In the WWTP of this study, N2O emissions accounted for over 60% of the total carbon footprint of the facility, on average. Different cycle configurations were implemented in the SBR aiming at reaching acceptable effluent values. Each cycle configuration consisted of sequences of aerated and non-aerated phases of different time length being controlled by the ammonium set-point fixed. Cycles with long aerated phases showed the largest N2O emissions, with the consequent increase in carbon footprint. Cycle configurations with intermittent aeration (aerated phases up to 20-30 min followed by short anoxic phases) were proven to effectively reduce N2O emissions, without compromising nitrification performance or increasing electricity consumption. This is the first study in which a successful operational strategy for N2O mitigation is identified at full-scale. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of the aerated structure on selected properties of freeze-dried hydrocolloid gels

NASA Astrophysics Data System (ADS)

Ciurzyńska, Agnieszka; Lenart, Andrzej

2016-01-01

The ability to create diverse structures and studies on the effect of the aerated structure on selected properties with the use of freeze-dried gels may provide knowledge about the properties of dried foods. Such gels can be a basis for obtaining innovative food products. For the gel preparation, 3 types of hydrocolloids were used: low-methoxyl pectin, a mixture of xanthan gum and locust-bean gum, and a mixture of xanthan gum and guar gum. Gels were aerated for 3 and 7 min, frozen at a temperature of -45°C 2 h-1, and freeze-dried at a temperature of 30°C. For the samples obtained, structure, porosity, shrinkage, rehydration, and colour were investigated. It was shown that the type of the hydrocolloid and aeration time influence the structure of freeze-dried gels, which determines such properties of samples as porosity, shrinkage, density, rehydration, and colour. The bigger pores of low-methoxyl pectin gels undergo rehydration in the highest degree. The delicate and aerated structure of gels with the mixture of xanthan gum and locust-bean gum was damaged during freeze-drying and shrinkage exhibited the highest value. Small pores of samples with the mixture of xanthan gum and guar gum were responsible for the lower rehydration properties, but the highest porosity value contributed to the highest lightness value.

Non-autoclaved aerated concrete with mineral additives

NASA Astrophysics Data System (ADS)

Il'ina, L. V.; Rakov, M. A.

2016-01-01

We investigated the effect of joint grinding of Portland cement clinker, silica and carbonate components and mineral additives to specific surface of 280 - 300 m2/kg on the properties (strength, average density and thermal conductivity) of non-autoclaved aerated concrete, and the porosity of the hardened cement paste produced from Portland cement clinker with mineral additives. The joint grinding of the Portland cement clinker with silica and carbonate components and mineral additives reduces the energy consumption of non-autoclaved aerated concrete production. The efficiency of mineral additives (diopside, wollastonite) is due to the closeness the composition, the type of chemical bonds, physical and chemical characteristics (specific enthalpy of formation, specific entropy) to anhydrous clinker minerals and their hydration products. Considering the influence of these additions on hydration of clinker minerals and formation of hardened cement paste structure, dispersed wollastonite and diopside should be used as mineral additives. The hardness and, consequently, the elastic modulus of diopside are higher than that of hardened cement paste. As a result, there is a redistribution of stresses in the hardened cement paste interporous partitions and hardening, both the partitions and aerated concrete on the whole. The mineral additives introduction allowed to obtain the non-autoclaved aerated concrete with average density 580 kg/m3, compressive strength of 3.3 MPa and thermal conductivity of 0.131 W/(m.°C).

Nitrogen removal on recycling water process of wastewater treatment plant effluent using subsurface horizontal wetland with continuous feed

NASA Astrophysics Data System (ADS)

Tazkiaturrizki, T.; Soewondo, P.; Handajani, M.

2018-01-01

Recycling water is a generic term for water reclamation and reuse to solve the scarcity of water. Constructed wetlands have been recognized as providing many benefits for wastewater treatment including water supply and control by recycling water. This research aims to find the best condition to significantly remove nitrogen using constructed wetland for recycling water of Bojongsoang Waste Water Treatment Plan (WWTP) effluent. Using media of soil, sand, gravel, and vegetation (Typha latifolia and Scirpus grossus) with an aeration system, BOD and COD parameters have been remarkably reduced. On the contrary, the removal efficiency for nitrogen is only between 50-60%. Modifications were then conducted by three step of treatment, i.e., Step I is to remove BOD/COD using Typha latifolia with an aeration system, Step II is todecrease nitrogen using Scirpus grossus with/without aeration, and Step III isto complete the nitrogen removal with denitrification process by Glycine max without aeration. Results of the research show that the nitrogen removal has been successfully increased to a high efficiency between 80-99%. The combination of aeration system and vegetation greatly affects the nitrogen removal. The vegetation acts as the organic nitrogen consumer (plant uptake) for amino acids, nitrate, and ammonium as nutrition, as well as theoxygen supplier to the roots so that aerobic microsites are formed for ammonification microorganisms.

Do radial oxygen loss and external aeration affect iron plaque formation and arsenic accumulation and speciation in rice?

PubMed Central

Wu, Chuan; Ye, Zhihong; Li, Hui; Wu, Shengchun; Deng, Dan; Zhu, Yongguan; Wong, Minghung

2012-01-01

Hydroponic experiments were conducted to investigate the effect of radial oxygen loss (ROL) and external aeration on iron (Fe) plaque formation, and arsenic (As) accumulation and speciation in rice (Oryza sativa L.). The data showed that there were significant correlations between ROL and Fe concentrations in Fe plaque produced on different genotypes of rice. There were also significant differences in the amounts of Fe plaque formed between different genotypes in different positions of roots and under different aeration conditions (aerated, normal, and stagnant treatments). In aerated treatments, rice tended to have a higher Fe plaque formation than in a stagnant solution, with the greatest formation at the root tip decreasing with increasing distances away, in accordance with a trend of spatial ROL. Genotypes with higher rates of ROL induced higher degrees of Fe plaque formation. Plaques sequestered As on rice roots, with arsenate almost double that with arsenite, leading to decreased As accumulation in both roots and shoots. The major As species detected in roots and shoots was arsenite, ranging from 34 to 78% of the total As in the different treatments and genotypes. These results contribute to our understanding of genotypic differences in As uptake by rice and the mechanisms causing rice genotypes with higher ROL to show lower overall As accumulation. PMID:22345639

Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.

PubMed

Ma, Yan; Du, Xiaoming; Shi, Yi; Xu, Zhu; Fang, Jidun; Li, Zheng; Li, Fasheng

2015-02-01

Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

Laboratory- and full-scale studies on the removal of pharmaceuticals in an aerated constructed wetland: effects of aeration and hydraulic retention time on the removal efficiency and assessment of the aquatic risk.

PubMed

Auvinen, Hannele; Gebhardt, Wilhelm; Linnemann, Volker; Du Laing, Gijs; Rousseau, Diederik P L

2017-09-01

Pharmaceutical residues in wastewater pose a challenge to wastewater treatment technologies. Constructed wetlands (CWs) are common wastewater treatment systems in rural areas and they discharge often in small water courses in which the ecology can be adversely affected by the discharged pharmaceuticals. Hence, there is a need for studies aiming to improve the removal of pharmaceuticals in CWs. In this study, the performance of a full-scale aerated sub-surface flow hybrid CW treating wastewater from a healthcare facility was studied in terms of common water parameters and pharmaceutical removal. In addition, a preliminary aquatic risk assessment based on hazard quotients was performed to estimate the likelihood of adverse effects on aquatic organisms in the forest creek where this CW discharges. The (combined) effect of aeration and hydraulic retention time (HRT) was evaluated in a laboratory-scale batch experiment. Excellent removal of the targeted pharmaceuticals was obtained in the full-scale CW (>90%) and, as a result, the aquatic risk was estimated low. The removal efficiency of only a few of the targeted pharmaceuticals was found to be dependent on the applied aeration (namely gabapentin, metformin and sotalol). Longer and the HRT increased the removal of carbamazepine, diclofenac and tramadol.

The Effects of Cannabis on Inpatient Agitation, Aggression, and Length of Stay.

PubMed

Johnson, Joseph M; Wu, Chris Y; Winder, Gerald Scott; Casher, Michael I; Marshall, Vincent D; Bostwick, Jolene R

2016-01-01

This study examines the association between cannabis use and the hospital course of patients admitted to the psychiatric inpatient unit with a diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder. Many confounding variables potentially contribute to the clinical presentation of hospitalized patients in the psychiatric unit. Illicit drug use, in particular, has been associated with acute agitation, and questions can be raised as to what lasting effects drug use prior to admission may have throughout a patient's hospital stay. Subjects with a discharge diagnosis of bipolar disorder, schizophrenia, schizoaffective disorder, or psychosis not otherwise specified (N = 201) were retrospectively identified, and those with positive results of urine drug screen for cannabis on admission were compared to negative counterparts. Agitation and aggression were measured using an adaptation of the Excited Component of the Positive and Negative Syndrome Scale (PANSS-EC). These markers were also quantified by comparing charted episodes of restraint and seclusion and administration of as needed medications, such as benzodiazepines and antipsychotics. Positive urine drug screen results for cannabis was correlated with young (p = .001) males (p = .003) with bipolar disorder (p = .009) exhibiting active manic symptoms (p = .003) at the time of admission. Cannabis use was further associated with a shorter length of stay (p = .008), agitation triggering adapted PANSS-EC nursing assessments (p = .029), and oral medications as needed (p = .002) for agitation. Cannabis use, as defined by positive urine drug screen results, was more common in patients with bipolar disorder and was accompanied by a higher incidence of inpatient agitation. Although these patients also had short hospital lengths of stay, there was no clear relationship between level of agitation and length of stay across all patient groups. One possible explanation for patients with bipolar disorder experiencing short lengths of stay is that their source of agitation may be more closely related to a complex effect of cannabis use rather than a sole etiology of mental illness. Inpatient clinicians should be aware of patient cannabis use proximate to admission.

Non-biodegradable landfill leachate treatment by combined process of agitation, coagulation, SBR and filtration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abood, Alkhafaji R.; Thi Qar University, Nasiriyah; Bao, Jianguo, E-mail: bjianguo888@126.com

2014-02-15

Highlights: • A novel method of stripping (agitation) was investigated for NH{sub 3}-N removal. • PFS coagulation followed agitation process enhanced the leachate biodegradation. • Nitrification–denitrification achieved by changing operation process in SBR treatment. • A dual filter of carbon-sand is suitable as a polishing treatment of leachate. • Combined treatment success for the complete treatment of non-biodegradable leachate. - Abstract: This study describes the complete treatment of non-biodegradable landfill leachate by combined treatment processes. The processes consist of agitation as a novel stripping method used to overcome the ammonia toxicity regarding aerobic microorganisms. The NH{sub 3}-N removal ratio wasmore » 93.9% obtained at pH 11.5 and a gradient velocity (G) 150 s{sup −1} within a five-hour agitation time. By poly ferric sulphate (PFS) coagulation followed the agitation process; chemical oxygen demand (COD) and biological oxygen demand (BOD{sub 5}) were removed at 70.6% and 49.4%, respectively at an optimum dose of 1200 mg L{sup −1} at pH 5.0. The biodegradable ratio BOD{sub 5}/COD was improved from 0.18 to 0.31 during pretreatment step by agitation and PFS coagulation. Thereafter, the effluent was diluted with sewage at a different ratio before it was subjected to sequencing batch reactor (SBR) treatment. Up to 93.3% BOD{sub 5}, 95.5% COD and 98.1% NH{sub 3}-N removal were achieved by SBR operated under anoxic–aerobic–anoxic conditions. The filtration process was carried out using sand and carbon as a dual filter media as polishing process. The final effluent concentration of COD, BOD{sub 5}, suspended solid (SS), NH{sub 3}-N and total organic carbon (TOC) were 72.4 mg L{sup −1}, 22.8 mg L{sup −1}, 24.2 mg L{sup −1}, 18.4 mg L{sup −1} and 50.8 mg L{sup −1} respectively, which met the discharge standard. The results indicated that a combined process of agitation-coagulation-SBR and filtration effectively eliminated pollutant loading from landfill leachate.« less

Electroconvulsive therapy (ECT) for treating agitation in dementia (major neurocognitive disorder) - a promising option.

PubMed

Glass, Oliver M; Forester, Brent P; Hermida, Adriana P

2017-05-01

Agitation in patients with dementia increases caretaker burden, increases healthcare costs, and worsens the patient's quality of life. Antipsychotic medications, commonly used for the treatment of agitation in patients with dementia have a box warning from the FDA for elevated mortality risk. Electroconvulsive therapy (ECT) has made significant advances over the past several years, and is efficacious in treating a wide range of psychiatric conditions. We provide a systematic review of published literature regarding the efficacy of ECT for the treatment of agitation in patients with dementia (major neurocognitive disorder). We searched PubMed, Medline, Google Scholar, UptoDate, Embase, and Cochrane for literature concerning ECT for treating agitation in dementia using the title search terms "ECT agitation dementia;" "ECT aggression dementia;" "ECT Behavior and Psychological Symptoms of Dementia;" and "ECT BPSD." The term "dementia" was also interchanged with "Major Neurocognitive Disorder." No time frame restriction was placed. We attempted to include all publications that were found to ensure a comprehensive review. We found 11 papers, with a total (N) of 216 patients. Limited to case reports, case series, retrospective chart review, retrospective case-control, and an open label prospective study, ECT has demonstrated promising results in decreasing agitation in patients with dementia. Patients who relapsed were found to benefit from maintenance ECT. Available studies are often limited by concomitant psychotropic medications, inconsistent use of objective rating scales, short follow-up, lack of a control group, small sample sizes, and publication bias. A future randomized controlled trial will pose ethical and methodological challenges. A randomized controlled trial must carefully consider the definition of usual care as a comparison group. Well-documented prospective studies and/or additional case series with explicit selection criteria, a wide range of outcome measures, and less selection bias of the study sample that may favor treatment response, is warranted. ECT may be a promising option for the treatment of aggression and agitation in patients with severe dementia who are refractory to other treatment options, but the limitations of available studies suggest that a cautious approach to future randomized controlled trials is warranted.

Sparging and agitation-induced injury of cultured animals cells: Do cell-to-bubble interactions in the bulk liquid injure cells?

PubMed

Michaels, J D; Mallik, A K; Papoutsakis, E T

1996-08-20

It has been established that the forces resulting from bubbles rupturing at the free air (gas)/liquid surface injure animal cells in agitated and/or sparged bioreactors. Although it has been suggested that bubble coalescence and breakup within agitated and sparged bioreactors (i.e., away from the free liquid surface) can be a source of cell injury as well, the evidence has been indirect. We have carried out experiments to examine this issue. The free air/liquid surface in a sparged and agitated bioractor was eliminated by completely filling the 2-L reactor and allowing sparged bubbles to escape through an outlet tube. Two identical bioreactors were run in parallel to make comparisons between cultures that were oxygenated via direct air sparging and the control culture in which silicone tubing was used for bubble-free oxygenation. Thus, cell damage from cell-to-bubble interactions due to processes (bubble coalescence and breakup) occurring in the bulk liquid could be isolated by eliminating damage due to bubbles rupturing at the free air/liquid surface of the bioreactor. We found that Chinese hamster ovary (CHO) cells grown in medium that does not contain shear-protecting additives can be agitated at rates up to 600 rpm without being damaged extensively by cell-to bubble interactions in the bulk of the bioreactor. We verified this using both batch and high-density perfusion cultures. We tested two impeller designs (pitched blade and Rushton) and found them not to affect cell damage under similar operational conditions. Sparger location (above vs. below the impeller) had no effect on cell damage at higher agitation rates but may affect the injury process at lower agitation intensities (here, below 250 rpm). In the absence of a headspace, we found less cell damage at higher agitation intensities (400 and 600 rpm), and we suggest that this nonintuitive finding derives from the important effect of bubble size and foam stability on the cell damage process. (c) 1996 John Wiley & Sons, Inc.

Recovery of ammonia and production of high-grade phosphates from digester effluents (municipal and livestock)

USDA-ARS?s Scientific Manuscript database

Phosphorus (P) recovery of anaerobically digested swine wastewater and side-stream municipal wastewater via magnesium precipitation was enhanced by combining it with the recovery of ammonia (NH3) through gas-permeable membranes and low-rate aeration. The low-rate aeration stripped the natural carbon...

DEMONSTRATION BULLETIN: LOW TEMPERATURE THERMAL AERATION (LTTA®) SYSTEM - CANONIE ENVIRONMENTAL SERVICES, INC.

EPA Science Inventory

The Low Temperature Thermal Aeration (LTTA®) process was developed by Canonie Environmental Services, Inc. (Canonie), as a treatment system that desorbs organic contaminants from soils by heating the soils up to 800 °F. The main components of the LTTA process include the follow...

Pilot Plant Demonstration of Stable and Efficient High Rate Biological Nutrient Removal with Low Dissolved Oxygen Conditions

EPA Science Inventory

Aeration in biological nutrient removal (BNR) processes accounts for nearly half of the total electricity costs at many wastewater treatment plants. Even though conventional BNR processes are usually operated to have aerated zones with high dissolved oxygen (DO) concentrations, r...

Processes to improve energy efficiency during pumping and aeration of recirculating water in circular tank systems

USDA-ARS?s Scientific Manuscript database

Conventional gas transfer technologies for aquaculture systems occupy a large amount of space, require considerable capital investment, and can contribute to high electricity demand. In addition, diffused aeration in a circular tank can interfere with the hydrodynamics of water rotation and the spee...

Activated Sludge. Student Manual. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Boe, Owen K.; Klopping, Paul H.

This student manual contains the textual material for a seven-lesson unit on activated sludge. Topic areas addressed in the lessons include: (1) activated sludge concepts and components (including aeration tanks, aeration systems, clarifiers, and sludge pumping systems); (2) activated sludge variations and modes; (3) biological nature of activated…