WorldWideScience

Sample records for m-1 settling basins

  1. Turbulent Flow Measurement in Vortex Settling Basin

    Directory of Open Access Journals (Sweden)

    Jafar Chapokpour

    2011-12-01

    Full Text Available This paper presents the findings of an experimental study on the three-dimensional turbulent flow field in vortex settling basin. An ADV (Acoustic Doppler Velocity Meter were used to catch 3D velocitycomponents inside the basin. Detailed measurements of time-averaged velocity components, turbulent intensity components and turbulent kinetic energy were determined at different radial sections of chamber. Also the normalized time averaged absolute velocity of 3D components in contour type exhibition were conducted and it was found that the absolute velocity generally is influenced by u component of flow. It trends from high magnitude in basin center to the constant magnitude in basin side wall. The normalized turbulent intensity ofthree components was investigated individually. It was found that intensity of 3D components in vicinity of central air core is higher than other regions, decreasing by moving towards basin sidewall except for the sections that influenced directly by entrance flow jet and sidewall exiting overflow. The results of turbulence kinetic energy also had the same interpretation like turbulence intensity and affected by the same boundary conditions which cover turbulence intensity of 3 velocity components overly.

  2. Construction of a cooling water inlet system with settling basin of Derna power plant station (Libya)

    Energy Technology Data Exchange (ETDEWEB)

    Glissmann, R.; Heimburg, A.M. von; Sinner, H.

    1985-03-01

    Construction of a cooling water intake system with settling basin. The extension of the power station at Derna, in Libya, necessitated the construction of a new cooling water intake system including screening facilities and a settling basin. Construction based on extensive prefabrication (precast concrete) was chosen. The precast reinforced units, ranging up to about 4000 t in weight, were towed on barges to the site of erection. At Derna these units were temporarily stored on the sea bed for several months, during which they were exposed to winter storms and rough sea. The major precast portion of the settling basin was constructed direct on the barge. On arrival at the site, the barge was sunk, allowing the precast unit, which was designed with sufficient buoyancy, to be floated off. The open unprotected coast required special arrangements for the protection of personnel, structures and equipment.

  3. Water and acrylamide monomer transfer rates from a settling basin to groundwaters.

    Science.gov (United States)

    Binet, Stéphane; Bru, Kathy; Klinka, Thomas; Touzé, Solène; Motelica-Heino, Mickael

    2015-05-01

    The aim of this paper was to estimate the potential leakage of acrylamide monomer, used for flocculation in a settling basin, towards the groundwaters. Surface-groundwater interactions were conceptualized with a groundwater transport model, using a transfer rate to describe the clogged properties of the interface. The change in the transfer rate as a function of the spreading of the clogged layer in the settling basin was characterized with respect to time. It is shown that the water and the Acrylamide transfer rate are not controlled by the spreading of the clogged layer until this layer fully covers the interface. When the clogged layer spreads out, the transfer rate remains in the same order of magnitude until the area covered reaches 80 %. The main flux takes place through bank seepage. In these early stage conditions of a working settling basin, the acrylamide flux towards groundwaters remains constant, at close to 10 g/year (±5).

  4. Extended characterization of M-Area settling basin and vicinity. Technical data summary. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Pickett, J B

    1985-10-01

    The Savannah River Plant M-Area settling basin, an unlined surface impoundment, has received process effluents from the M-Area fuel and target fabrication facilities since 1958. The waste effluents have contained metal degreasing agents (chlorinated hydrocarbons), acids, caustics, and heavy metals. Data analyses are provided.

  5. Computational fluid dynamics modelling of flow and particulate contaminants sedimentation in an urban stormwater detention and settling basin.

    Science.gov (United States)

    Yan, Hexiang; Lipeme Kouyi, Gislain; Gonzalez-Merchan, Carolina; Becouze-Lareure, Céline; Sebastian, Christel; Barraud, Sylvie; Bertrand-Krajewski, Jean-Luc

    2014-04-01

    Sedimentation is a common but complex phenomenon in the urban drainage system. The settling mechanisms involved in detention basins are still not well understood. The lack of knowledge on sediment transport and settling processes in actual detention basins is still an obstacle to the optimization of the design and the management of the stormwater detention basins. In order to well understand the sedimentation processes, in this paper, a new boundary condition as an attempt to represent the sedimentation processes based on particle tracking approach is presented. The proposed boundary condition is based on the assumption that the flow turbulent kinetic energy near the bottom plays an important role on the sedimentation processes. The simulated results show that the proposed boundary condition appears as a potential capability to identify the preferential sediment zones and to predict the trapping efficiency of the basin during storm events.

  6. Assessment of Jet Erosion for Potential Post-Retrieval K-Basin Settled Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Wells, Beric E.; Enderlin, Carl W.; Gauglitz, Phillip A.; Peterson, Reid A.

    2009-09-29

    Packaged K-Basin sludge will be transported to the T Plant on the Hanford Site where it will be interim stored. The sludge will be retrieved from the storage containers and processed for disposal. A sample of high uranium content canister sludge, designated 96-13, "self-cemented" during laboratory storage. This sample was uncharacteristically strong compared to expected K-Basin material. The purpose for this work is to evaluate the potential retrieval of such sludge after storage at the T Plant via jet erosion. The specific objectives of this report are to determine the modes of erosion and the methods used to measure/assess the erodibility parameters of sludge and identify those parameters applicable to jet erosion. The erodibility parameters of sample 96-13 are characterized to the extent possible. These objectives have been met based on literature review, past experience at Pacific Northwest National Laboratory, and observation of sample 96-13 video during hot-cell activities.

  7. Evaluating DNAPL Source and Migration Zones: M-Area Settling Basin and the Western Sector of A/M Area, Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D.G.

    2001-09-11

    The objective of this investigation is to critically evaluate previous characterization and remediation data to determine the current extent and distribution of DNAPL associated with releases at the M-Area Basin within A/M Area. The primary objective of the effort is to develop an approximate recommendation for the target treatment location and volume near the M Area Settling Basin. Through this analysis the final objective is to identify those subsurface regions having specific geometry and character necessary to cost-effectively deploy DNAPL specific remediation alternatives.

  8. Modeling Precipitating Tub (Settling Basin For Reduction Sedimentation Effect in Irrigation Channel at Micro Hydro Power (Case Study At Gorontalo Province Irrigation Channel

    Directory of Open Access Journals (Sweden)

    Arifin Matoka

    2016-05-01

    Full Text Available Potential irrigation channels widely in Indonesia and suitable for turbine type Plopeler Open Flume. From observation this sedimentation processes was effect on turbin and quality electric power generated. This study was determine the relationship effect of sedimentation on parameter MHP and modeling sedimentation basin to reduce its influence. The settling basin modeling into 3 design models and 2 codition,. MHP conditions in the rain without modeling with the data voltage deviation Vd = 17.6%, frequency deviation Fd = 6.8% and rotation deviation Nd = 6.8% at concentration sedimentation between 2.551 C (g/l and 3.864 (g/l where the value of C category (C > 2.5 (g/l (bad sedimentation MHP operates abnormally. By modeling setling basin designs III at time rain, was obtained deviation voltage Vd = 3%, deviation frequency Fd = 1% and the deviation of rotation Nd = 1% at a concentration of sedimentation C between 1.160 (g/l and 1.340 (g/l in which the value C category (under C <2.5 (g/l, condition of the MHP normal operating. This research beneficial to reduce the cost of investment the load control electronic equipment and reference in the development National Irrigation Project.

  9. Time-series measurements of settling particulate matter in Alfonso Basin, La Paz Bay, southwestern Gulf of California

    Science.gov (United States)

    Silverberg, Norman; Aguirre-Bahena, Fernando; Mucci, Alfonso

    2014-08-01

    More than 200 sediment trap samples were collected at 310 or 360 m depth during 2002-2009 from the center of the 410 m-deep Alfonso Basin in La Paz Bay, an arid, subtropical embayment of the southern Gulf of California. Sample splits were analyzed for total mass flux (TMF), particulate organic carbon (POC), inorganic carbon (CaCO3) and opal (biogenic silica BioSi). The lithogenic (Litho) and biogenic fluxes (Biogen), but especially the particulate organic matter (POM) and CaCO3, fluxes are relatively high compared with those recorded in a number of other coastal basins at depths less than ~500 m. The average yearly Litho fluxes (mean of 133±158 g m-2 yr-1) are well correlated with the frequency of strong wind gusts and reflect the relative proximity of the mooring to shore and the importance of eolian transport. The sedimentation patterns are influenced by monsoonal shifts-cool temperatures and strong northerly winds in late fall and winter sustain a well-mixed deep surface layer and high lithogenic fluxes, whereas progressive heating and relatively weak southerlies in summer and fall lead to a shallower, more-stratified surface layer with lower nutrient levels, limited productivity and generally low particulate fluxes. There is considerable interannual variability in the size of the various fluxes. This is likely related to a number of regional and internal factors whose timing, intensity and interactions remain to be resolved. Although there is an inverse relationship between SST and satellite-derived net primary production (NPP) estimates, no correlation was found between NPP and the POC, CaCO3 and BioSi fluxes (r20.05). Significant correlations (p<0.001) do exist, however, between the POC flux and the total mineral flux as well as with the CaCO3, Litho and BioSi fluxes (r=0.86, 0.82, 0.79 and 0.69, respectively). As suggested by the ballast ratio hypothesis, the strength of these correlations follows the relative density of the individual ballast components

  10. The formation of early settled villages and the emergence of leadership: A test of three theoretical models in the Rio Ilave, Lake Titicaca Basin, southern Peru

    Science.gov (United States)

    Craig, Nathan Mcdonald

    Despite obvious necessities for understanding later developments in the region, Preceramic cultures in the Titicaca Basin are poorly understood due to lacking empirical data. This dissertation focuses on examination of two processes occurring in the Rio Ilave drainage during the Late 5000--3100 B.C.E. (6000--4400 B.P.) and Terminal 3100--1500 B.C.E. Archaic (4400--3200 B.P.): the formation of settled villages and the emergence of leadership. These processes are tested against theoretical predictions derived from: population resource imbalance, human behavioral ecology, and agency theories. Resource imbalance theory predicts appearance of density dependent adaptive problems prior to major cultural transformations. Human behavioral ecology predicts increased dietary diversity and incorporation of greater processing costs occuring coincidentally with reduced residential mobility. Symbolic mate value advertising is a predicted leadership strategy. Agency theory predicts internal sources of social tension, potentially independent of external forces, as primary causes of cultural change. Feast hosting and the formation political economy are expected to be central to both social processes investigated from this perspective. Local paleoclimatic proxies suggest aridity from ca 4000--2000 B.C.E. Reanalysis of pedestrian survey data indicate population growth during the Late Archaic. Excavation and ground penetrating radar survey at Pirco and Jiskairumoko demonstrate reduced residential mobility and increased evidence for social differentiation appearing during the Late Archaic's (before 3000 B.C.E.) end. New cultural patterns include: pithouses, more groundstone, internal storage, costly non-local artifacts, domesticated plants and animals, costly grave goods, and use of ochre in symbolic contexts. No clear cut evidence for inter-community promotional feasting was identified but some finds suggest intra-community alliance feasts. By the end of the Terminal Archaic ca. 1500 B

  11. Numerical Modelling of Flow and Settling in Secondary Settling Tanks

    DEFF Research Database (Denmark)

    Dahl, Claus Poulsen

    This thesis discusses the development of a numerical model for the simulation of secondary settling tanks. In the first part, the status on the development of numerical models for settling tanks and a discussion of the current design practice are presented. A study of the existing numerical models...... and design practice proved a demand for further development to include numerical models in the design of settling tanks, thus improving the future settling tanks....

  12. Numerical Modelling of Flow and Settling in Secondary Settling Tanks

    DEFF Research Database (Denmark)

    Dahl, Claus Poulsen

    This thesis discusses the development of a numerical model for the simulation of secondary settling tanks. In the first part, the status on the development of numerical models for settling tanks and a discussion of the current design practice are presented. A study of the existing numerical models...... and design practice proved a demand for further development to include numerical models in the design of settling tanks, thus improving the future settling tanks....

  13. What is 'settled Science'?

    Science.gov (United States)

    Brown, M.

    2013-12-01

    Republican strategist Frank Luntz famously advised party leaders to emphasize the lack of ';scientific certainty' about global warming because, once the public became convinced of a scientific consensus on global warming, they would accept it and policies responding to it. But philosophical work on scientific methodology puts absolute certainty out of reach. Today almost all philosophers are fallibilists, holding that every belief is subject to correction. Does it follow that an honest report of what science has to say about any topic cannot claim that the matter is settled? I defend a more confident view: much of what science has to say about the world is settled. On this view, settled science doesn't require philosophical certainty. Instead, it is based on stable agreement and practical reliability--values central to C.S. Peirce's account of the scientific method. Defending this position requires care over changes in theory that can undermine the language in which these settled points were initially expressed. It also requires epistemic modesty, since our confidence in any claim, including observational claims, depends on a kind of induction, and could, in principle, be undermined. Interestingly, this line of thought also suggests many of the central claims the historical sciences make about our world are more stable and reliable than the more theory-dependent claims we think of as central to the foundations of physics. David Hume undermined philosophical certainty about causal laws when he argued that, no matter how many times we make observations confirming a law, it could still fail the next test. This point is sometimes confused with healthy scientific skepticism, but Hume's worry has a much broader scope than scientific skepticism. For Hume each instance of a causal relation was doubtful, no matter how similar to previous instances. But scientists are diffident about applying a well-tested law only when the circumstances differ. For instance, particle

  14. Pinning Down Gravitational Settling

    CERN Document Server

    Korn, A J; Grundahl, F; Barklem, P; Gustafsson, B; Korn, Andreas J.; Piskunov, Nikolai; Grundahl, Frank; Barklem, Paul; Gustafsson, Bengt

    2006-01-01

    We analyse high-resolution archival UVES data of turnoff and subgiant stars in the nearby globular cluster NGC 6397 ([Fe/H] = -2). Balmer-profile analyses are performed to derive reddening-free effective temperatures. Due to the limited S/N and uncertainties related to blaze removal, we find the data quality insufficient to exclude the existence of gravitational settling. If the newly derived effective temperatures are taken as a basis for an abundance analysis, the photospheric iron (Fe II) abundance in the turnoff stars is 0.11 dex lower than in the (well-mixed) subgiants.

  15. Limit of stokesian settling concentration characterizes sludge settling velocity.

    Science.gov (United States)

    Mancell-Egala, William A S K; Kinnear, David J; Jones, Kimberly L; De Clippeleir, Haydée; Takács, Imre; Murthy, Sudhir N

    2016-03-01

    Flocculent settling (stokesian) is predominant within ideally operating clarifiers, and the shift to 'slower' hindered settling (non-stokesian) causes both failure and poor effluent quality. Therefore, a new metric for settling characteristics was developed and classified as Limit of Stokesian Settling (LOSS). The technique consisted of determining the total suspended solids (TSS) concentration at which mixed liquor settling characteristics transition from stokesian to non-stokesian settling. An image analytical technique was developed with the aid of MATLAB(®) to identify this transition. The MATLAB tool analyzed RGB images from video, and identified the presence of an interface by a dramatic shift in the Red indices. LOSS data for Secondary activated-sludge systems were analyzed for a period of 60 days at the Blue Plains Advanced Wastewater Treatment Plant. LOSS for secondary systems typically occurred between 600 and 700 mg TSS/L but reached 1000 mg TSS/L for a good settling secondary sludge and 500 mg TSS/L for a poor settling secondary sludge, settling quality was based on hindered settling rates. In addition, LOSS was collected for granular systems seeded with cyclone underflow from Strass Wastewater Treatment Plant, it was observed that LOSS was higher for granular systems ranging from 1600 to 5500 mg TSS/L for low and high levels of granulation, respectively. The monovalent to divalent cation ratio (M/D) was increased with the addition of sodium ions to deteriorate settling properties. Samples adjusted with higher M/D consistently had 100 mg TSS/L (15%) decrease in LOSS from the control. LOSS numbers collected experimentally were validated with the Takacs et al. (1991) settling model. When compared to flux curves with small changes in sludge matrix, LOSS was proven to be faster at characterizing hindered settling velocity and was less erratic. This is the first time a measurement method has been developed to characterize the transition from stokesian

  16. Mercury, Methylmercury, and Other Constituents in Sediment and Water from Seasonal and Permanent Wetlands in the Cache Creek Settling Basin and Yolo Bypass, Yolo County, California, 2005-06

    Science.gov (United States)

    Marvin-DiPasquale, Mark; Alpers, Charles; Fleck, Jacob

    2009-01-01

    This report presents surface water and surface (top 0-2 cm) sediment geochemical data collected during 2005-2006, as part of a larger study of mercury (Hg) dynamics in seasonal and permanently flooded wetland habitats within the lower Sacramento River basin, Yolo County, California. The study was conducted in two phases. Phase I represented reconnaissance sampling and included three locations within the Cache Creek drainage basin; two within the Cache Creek Nature Preserve (CCNP) and one in the Cache Creek Settling Basin (CCSB) within the creek's main channel near the southeast outlet to the Yolo Bypass. Two additional downstream sites within the Yolo Bypass Wildlife Area (YBWA) were also sampled during Phase I, including one permanently flooded wetland and one seasonally flooded wetland, which had began being flooded only 1-2 days before Phase I sampling. Results from Phase I include: (a) a negative correlation between total mercury (THg) and the percentage of methylmercury (MeHg) in unfiltered surface water; (b) a positive correlation between sediment THg concentration and sediment organic content; (c) surface water and sediment THg concentrations were highest at the CCSB site; (d) sediment inorganic reactive mercury (Hg(II)R) concentration was positively related to sediment oxidation-reduction potential and negatively related to sediment acid volatile sulfur (AVS) concentration; (e) sediment Hg(II)R concentrations were highest at the two YBWA sites; (f) unfiltered surface water MeHg concentration was highest at the seasonal wetland YBWA site, and sediment MeHg was highest at the permanently flooded YBWA site; (g) a 1,000-fold increase in sediment pore water sulfate concentration was observed in the downstream transect from the CCNP to the YBWA; (h) low sediment pore water sulfide concentrations (<1 umol/L) across all sites; and (i) iron (Fe) speciation data suggest a higher potential for microbial Fe(III)-reduction in the YBWA compared to the CCSB. Phase II

  17. Nonlinear programming technique for analyzing flocculent settling data.

    Science.gov (United States)

    Rashid, Md Mamunur; Hayes, Donald F

    2014-04-01

    The traditional graphical approach for drawing iso-concentration curves to analyze flocculent settling data and design sedimentation basins poses difficulties for computer-based design methods. Thus, researchers have developed empirical approaches to analyze settling data. In this study, the ability of five empirical approaches to fit flocculent settling test data is compared. Particular emphasis is given to compare rule-based SETTLE and rule-based nonlinear programming (NLP) techniques as a viable alternative to the modeling methods of Berthouex and Stevens (1982), San (1989), and Ozer (1994). Published flocculent settling data are used to test the suitability of these empirical approaches. The primary objective, however, is to determine if the results of a NLP optimization technique are more reliable than those of other approaches. For this, mathematical curve fitting is conducted and the modeled concentration data are graphically compared to the observed data. The design results in terms of average solid removal efficiency as a function of detention times are also compared. Finally, the sum of squared errors values from these approaches are compared. The results indicate a strong correlation between observed and NLP modeled concentration data. The SETTLE and NLP approaches tend to be more conservative at lower retention times and less conservative at longer retention times. The SETTLE approach appears to be the most conservative. In terms of sum of squared errors values, NLP appears to be rank number one (i.e., best model) for eight data sets and number two for six data sets among 15 data sets. Therefore, NLP is recommended for analyzing flocculent settling data as a logical extension of other approaches. The NLP approach is further recommended as it is an optimization technique and uses conventional mathematical algorithms that can be solved using widely available software such as EXCEL and LINGO.

  18. Dispersal, settling and layer formation.

    Science.gov (United States)

    Caffrey, James R; Hughes, Barry D; Landman, Kerry A

    2011-07-01

    Motivated by examples in developmental biology and ecology, we develop a model for convection-dominated invasion of a spatial region by initially motile agents which are able to settle permanently. The motion of the motile agents and their rate of settling are affected by the local concentration of settled agents. The model can be formulated as a nonlinear partial differential equation for the time-integrated local concentration of the motile agents, from which the instantaneous density of settled agents and its long-time limit can be extracted. In the limit of zero diffusivity, the partial differential equation is of first order; for application-relevant initial and boundary-value problems, shocks arise in the time-integrated motile agent density, leading to delta-function components in the motile agent density. Furthermore, there are simple solutions for a model of successive layer formation. In addition some analytic results for a one-dimensional system with non-zero diffusivity can also be obtained. A case study, both with and without diffusion, is examined numerically. Some important predictions of the model are insensitive to the specific settling law used and the model offers insight into biological processes involving layered growth or overlapping generations of colonization.

  19. 厄瓜多尔奥连特盆地白垩系M1油藏沉积储层新认识%New understanding of sedimentation and reservoir characteristics of M1zone in Cretaceous strata of Oriente Basin,Ecuador

    Institute of Scientific and Technical Information of China (English)

    陈诗望; 姜在兴; 滕彬彬; 徐德军

    2012-01-01

    The paleo-geomorphology of Block 14and 17which is high in the east and low in the west in the region is further characterized and an N-S trend paleo-barrier island is identified in H oilfield according to sand thickness,structural inversion,core and kaolinite content in drilled wells.The sedimentary microfacies of M1are described under the guidance of sedimentary model.The results show that H oilfield is mud flat and mixed flat,N oilfield is sand flat and tidal channel,K-S oilfield is located in sub-tidal zone while W oilfield deposits tidal-dominated delta sediments.The analysis of reservoir and oil-bearing characteristics controlled by microfacies indicates that tidal channel and sand flat sandstones are favorable reservoirs with mid-high porosity and extra-high permeability,mainly distributing in the slope.Meanwhile,reservoirs in mixed flat and mud flat with thin sandstone and limited distribution are poor oil layers or dry layers on the top of the structure.Therefore,structural-lithological oil reservoirs are formed due to the special matching relationship between both structure and reservoir.%在14、17区块古地貌东高西低的区域性认识基础上,根据砂岩厚度分布规律、构造反演、岩心以及录井中高岭石的相对含量,确定了古地貌特征,指出在H油田存在南北向古海岛。结合沉积模式,描述了M1层沉积微相展布。结果表明:H油田位于泥坪和混合坪亚相,N油田位于砂坪亚相和潮道发育区,K—S油田位于潮下带,W油田为潮控三角洲沉积。并对沉积相控制的储层特征和含油性特征进行了分析,指出有利储层为潮道和砂坪砂岩,为中高孔特高渗储层,此类储层分布在目前构造的斜坡部位;混合坪和泥坪中储层分布局限,易形成差油层或干层,此类储层分布在目前构造顶部。由于构造和储层的特殊匹配关系,形成构造岩性复合油藏。

  20. Sedimentation process and design of settling systems

    CERN Document Server

    De, Alak

    2017-01-01

    This book is designed to serve as a comprehensive source of information of sedimentation processes and design of settling systems, especially as applied to design of such systems in civil and environmental engineering. The book begins with an introduction to sedimentation as a whole and goes on to cover the development and details of various settling theories. The book traces the chronological developments of the comprehensive knowledge of settling studies and design of settling systems from 1889.A new concept of 'Velocity Profile Theorem', tool for settling problem analysis, has been employed to the analysis of the phenomenon of short circuiting. Complete theory of tube settling has been developed and its application to the computation of residual solids from the assorted solids through the same has been demonstrated. Experimental verification of the tube settling theory has also been presented. Field-oriented compatible design and operation methodology of settling system has been developed from the detailed...

  1. GSM(m,1)(m=1,2)模型的数值解%Numeriacl Solution of GSM (m, 1)(m= 1,2)Model

    Institute of Scientific and Technical Information of China (English)

    吴强; 刘炳琪

    2001-01-01

    The prediction accuracy can be improved by using the spline function to correct the residue of GM (m,1)(m=1,2). Numerical Solution of GSM (m,1)(m=1,2)Modle is given.%本文用样条函数对GM(m,1)(m=1,2)模型的残差序列进行插值拟合,得到GSM(m,1)(m=1,2)模型的数值解.

  2. Settling of copper drops in molten slags

    Science.gov (United States)

    Warczok, A.; Utigard, T. A.

    1995-02-01

    The settling of suspended metal and sulfide droplets in liquid metallurgical, slags can be affected by electric fields. The migration of droplets due to electrocapillary motion phenomena may be used to enhance the recovery of suspended matte/metal droplets and thereby to increase the recovery of pay metals. An experimental technique was developed for the purpose of measuring the effect of electric fields on the settling rate of metallic drops in liquid slags. Copper drops suspended in CaO-SiO2-Al2O3-Cu2O slags were found to migrate toward the cathode. Electric fields can increase the settling rate of 5-mm-diameter copper drops 3 times or decrease the settling until levitation by reversal of the electric field. The enhanced settling due to electric fields decreases with increasing Cu2O contents in the slag.

  3. Settling characteristics of some Indian fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Jain, M.K.; Sastry, B.S. [Indian Institute of Technology, Kharapur (India). Dept. of Mining Engineering

    2003-07-01

    The paper examines the aspects of the solid liquid separation (settling characteristics) of some of the fly ash obtained from coal-fired power plants in India. The application of a coagulating or flocculating agent (polymer) to improve the two properties as indicated is a typical industrial practice. The sources for this study comprise of fly ash, pond ash, and bottom ash and the settling characteristics are studied in conjunction with the flocculating agent polyacrylamide. 4 refs., 4 figs., 3 tabs.

  4. Measuring of Settling Velocity of Fine Sediment Using a Recirculated Settling Column

    DEFF Research Database (Denmark)

    Johansen, Claus; Larsen, Torben

    1998-01-01

    The paper describes a new experimental method for the measurement of the settling velocity of fine sediments. The method includes determination of the influence of turbulence and concentration. The paper also illustrates the method by giving results of the settling velocity of kaolinite for varyi...

  5. Measurement of Settling Velocity of Fine Sediment using a Recirculated Settling Column

    DEFF Research Database (Denmark)

    Johansen, C.; Larsen, Torben

    1997-01-01

    The paper describes a new experimental method for the measurement of the settling velocity of fine sediments. The method includes determination of the influence of turbulence and concentration. The paper also illustrates the method by giving results of the settling velocity of kaolinite for varyi...

  6. Computer simulation of free settling and skeletal settling during liquid phase sintering

    Directory of Open Access Journals (Sweden)

    Nikolić Z.S.

    2006-01-01

    Full Text Available In recent years, a range of computer simulation models leading to a better understanding of liquid phase sintering phenomena, have been developed with the aim of simulating the detailed evolution of microstructure during grain growth. Some liquid phase sintered materials show both macrostructural and microstructural effects associated with gravity force. Therefore we will develop a numerical procedure for the estimation of how much gravity will influence domain (two-dimensional particle representation growth, domain boundary migration and solid skeleton formation due to gravity induced segregation during liquid phase sintering. The method used for the simulation of a gravity field will be based on the settling procedure. Gravity induced settling will be separated into two stages - Free Settling and Skeletal Settling. Isolated solid phase domains fall under gravity and slide down over the already settled domains (free settling. During settling they make point contacts with each other. Necks between them then form and start to grow until the equilibrium dihedral angle between the domain boundaries and the liquid is established. Thus a solid skeleton forms and skeletal settling of a connected solid structure takes place. .

  7. Measurement of Settling Velocity of Fine Sediment using a Recirculated Settling Column

    DEFF Research Database (Denmark)

    Johansen, C.; Larsen, Torben

    1997-01-01

    The paper describes a new experimental method for the measurement of the settling velocity of fine sediments. The method includes determination of the influence of turbulence and concentration. The paper also illustrates the method by giving results of the settling velocity of kaolinite for varying...

  8. On-line Measurements of Settling Charateristics in Activated Sludge

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Larsen, Torben

    1997-01-01

    An on-line settling column for measuring the dynamic variations of settling velocity of activated sludge has been developed. The settling column is automatic and self-cleansing insuring continuous and reliable measurements. The settling column was tested on sludge from a batch reactor where sucrose...... was added as an impulse to activated sludge. The continuous measurement of settling velocity revealed a highly dynamic response after the sucrose was added. The result were verified with simultaneous measurement of the initial settling rate. A 200 hour experiment showed variations in settling velocity...

  9. Competing jurisdictions : settling land claims in Africa

    NARCIS (Netherlands)

    Evers, Sandra; Spierenburg, M.; Wels, H.

    2005-01-01

    The papers included in this volume were earlier presented at a conference on the settlement of land claims in Africa, which was held in Amsterdam in September 2003. The papers are written primarily from an anthropological perspective. Contributions: Introduction: competing jurisdictions: settling la

  10. Competing jurisdictions : settling land claims in Africa

    NARCIS (Netherlands)

    Evers, S.; Spierenburg, M.; Wels, H.

    2005-01-01

    The papers included in this volume were earlier presented at a conference on the settlement of land claims in Africa, which was held in Amsterdam in September 2003. The papers are written primarily from an anthropological perspective. Contributions: Introduction: competing jurisdictions: settling

  11. M$_1$ - M* correlation in galaxy clusters

    CERN Document Server

    Trevese, D; Appodia, B

    1994-01-01

    Photographic F band photometry of a sample of 36 Abell clusters has been used to study the relation between the magnitude M_1 of the brightest cluster member and the Schechter function parameter M^*. Clusters appear segregated in the M_1-M^* plane according to their Rood \\& Sastry class. We prove on a statistical basis that on average, going from early to late RS classes, M_1 becomes brighter while M^* becomes fainter. The result agrees with the predictions of galactic cannibalism models, never confirmed by previous analyses.

  12. Segregation and differential settling in flocculated tailings

    Energy Technology Data Exchange (ETDEWEB)

    Farinato, R.S.; Mahmoudkhani, A.; Fenderson, T.; Watson, P. [Kemira, Atlanta, GA (United States)

    2010-07-01

    Untreated oil sands tailings have a high solids content, have poor dewaterability, and contain no aggregates. This PowerPoint presentation investigated segregation and differential settling in flocculated tailings. Tailings were treated with gypsum and various polymers. Cylinder settling, dynamic rheometry, particle size analysis, and microscopy techniques were used to characterize the composite tailings. The particles sizes of the samples were evaluated in relation to shear rate, bed depth, and treatment. The study showed that the gypsum-treated tailings had small aggregates, size stratification, a high solids content, and poor dewaterability. The polymer N-treated tailings had the lowest solids content, good dewaterability, and weak aggregates. The polymer A-treated tailings had a low solids content, very good dewaterability, and strong aggregates. The addition of a coagulant to the polymer-A treated tailings provided weaker aggregates and a higher solids content. tabs., figs.

  13. Full Scale Performance of Primary Settling Tanks

    OpenAIRE

    Ahmad, Shamim; Murad, M.; Javed, K. H.

    1989-01-01

    The characteristics and the flowrate of municipal wastewater from the city of Doha, located in the Arabian Gulf have been studied to examine their effect on the performance of the primary settling tanks at the local sewage treatment plant. The wastweater is predominantly domestic and characterized by low suspended solids concentration but high total dissolved solids. The high temperature of the wastewater and long flowtime in the sewerage system turn it septic. The performance efficiency o...

  14. Reduced particle settling speed in turbulence

    CERN Document Server

    Fornari, Walter; Sardina, Gaetano; Brandt, Luca

    2016-01-01

    We study the settling of finite-size rigid spheres in sustained homogeneous isotropic turbulence (HIT) using Direct Numerical Simulations. In particular, an immersed boundary method is used to account for the dispersed solid phase. We study semi-dilute suspensions of spheres at different Galileo numbers, Ga. The Galileo number is the ratio between buoyancy and viscous forces, and is here varied via the solid-to-fluid density ratio. The focus is on particles that are slightly heavier than the fluid. We find that in HIT, the mean settling speed is less than in quiescent fluid and it reduces by 6 to 60\\% with respect to the terminal velocity of an isolated sphere in quiescent fluid "Vt", as the ratio between "Vt" and the turbulent velocity fluctuations u' is decreased. Analysing the fluid-particle relative motion, we find that the mean settling speed is progressively reduced while reducing due to the increase of the vertical drag induced by the particle cross-flow velocity. Unsteady effects contribute to the mea...

  15. Design aspects and performance of a settling tube system

    NARCIS (Netherlands)

    Slot, R.E.; Geldof, H.J.

    1979-01-01

    The DUST (Delft University Settling Tube) is a settling tube system intended to analyse particle size (settling velocity) of sand ranging from 0.06 mm to 2 mm, with the sample mass varying from 0.5 g to 20 g. The main parts of the system are (see fig. 1): a. the sample introduction device (venetian

  16. The Settling and Compaction of Nuclear Waste Slurries

    Energy Technology Data Exchange (ETDEWEB)

    MACLEAN, G.T.

    1999-11-15

    The settling and compaction of simulated and real nuclear waste slurries were extensively studied. Experiments were carried out with simulated wastes at laboratory and large-scale sizes, and the results compared. A model of settling was derived and a method developed to correlate and scale-up settling data for different slurries and vessel sizes.

  17. Characterization of Compass M-1 signals

    NARCIS (Netherlands)

    Hauschild, A.; Montenbruck, O.; Sleewaegen, J.-M.; Huisman, L.; Teunissen, P.J.G.

    2011-01-01

    An analysis of observations from China’s first medium earth orbit satellite Compass M-1 is presented, with main focus on the first orbit and clock solution for this satellite. The orbit is computed from laser ranging measurements. Based on this orbit solution, the apparent clock offset is estimated

  18. On the hindered settling of sand-mud suspensions

    Science.gov (United States)

    Spearman, Jeremy; Manning, Andrew J.

    2017-04-01

    Hindered settling, the process by which the settling of sediment particles becomes impeded due to the proximity of other sediment particles, can be an important process for the coastal modeller, especially in highly muddy environments. It is also a significant process in other disciplines such as chemical engineering, the modelling of debris flow, the study of turbidites, piping of slurries and the understanding of processes occurring within a dredger hopper. This study first examines the hindered settling behaviour of monodisperse suspensions in order to create a framework for polydisperse hindered settling that works for both non-cohesive and cohesive suspensions. The Richardson-Zaki equation is adapted to make it compatible with the changes with viscosity that occur near the point at which suspensions become solid. The modified monodisperse settling equation is then compared to data for hindered settling of cohesive suspensions and shown to be consistent with the transition between hindered settling and the initial permeability phase of consolidation. Based on the monodisperse framework developed initially, this paper proposes a hindered settling model for sand/mud mixtures which is based on a modification of the Masliyah (1979) and Lockett and Bassoon (1979) hindered settling equation. The model is shown to reproduce the hindered settling of a variety of different sediment mixtures whilst reducing the extent of empiricism often associated with the modelling of polydisperse hindered settling of mud/sand mixtures.

  19. Analytic closures for M1 neutrino transport

    Science.gov (United States)

    Murchikova, E. M.; Abdikamalov, E.; Urbatsch, T.

    2017-08-01

    Carefully accounting for neutrino transport is an essential component of many astrophysical studies. Solving the full transport equation is too expensive for most realistic applications, especially those involving multiple spatial dimensions. For such cases, resorting to approximations is often the only viable option for obtaining solutions. One such approximation, which recently became popular, is the M1 method. It utilizes the system of the lowest two moments of the transport equation and closes the system with an ad hoc closure relation. The accuracy of the M1 solution depends on the quality of the closure. Several closures have been proposed in the literature and have been used in various studies. We carry out an extensive study of these closures by comparing the results of M1 calculations with precise Monte Carlo calculations of the radiation field around spherically symmetric protoneutron star models. We find that no closure performs consistently better or worse than others in all cases. The level of accuracy that a given closure yields depends on the matter configuration, neutrino type and neutrino energy. Given this limitation, the maximum entropy closure by Minerbo on average yields relatively accurate results in the broadest set of cases considered in this work.

  20. M1 muscarinic receptor activation mediates cell death in M1-HEK293 cells.

    Science.gov (United States)

    Graham, E Scott; Woo, Kerhan K; Aalderink, Miranda; Fry, Sandie; Greenwood, Jeffrey M; Glass, Michelle; Dragunow, Mike

    2013-01-01

    HEK293 cells have been used extensively to generate stable cell lines to study G protein-coupled receptors, such as muscarinic acetylcholine receptors (mAChRs). The activation of M1 mAChRs in various cell types in vitro has been shown to be protective. To further investigate M1 mAChR-mediated cell survival, we generated stable HEK293 cell-lines expressing the human M1 mAChR. M1 mAChRs were efficiently expressed at the cell surface and efficiently internalised within 1 h by carbachol. Carbachol also induced early signalling cascades similar to previous reports. Thus, ectopically expressed M1 receptors behaved in a similar fashion to the native receptor over short time periods of analysis. However, substantial cell death was observed in HEK293-M1 cells within 24 h after carbachol application. Death was only observed in HEK cells expressing M1 receptors and fully blocked by M1 antagonists. M1 mAChR-stimulation mediated prolonged activation of the MEK-ERK pathway and resulted in prolonged induction of the transcription factor EGR-1 (>24 h). Blockade of ERK signalling with U0126 did not reduce M1 mAChR-mediated cell-death significantly but inhibited the acute induction of EGR-1. We investigated the time-course of cell death using time-lapse microscopy and xCELLigence technology. Both revealed the M1 mAChR cytotoxicity occurs within several hours of M1 activation. The xCELLigence assay also confirmed that the ERK pathway was not involved in cell-death. Interestingly, the MEK blocker did reduce carbachol-mediated cleaved caspase 3 expression in HEK293-M1 cells. The HEK293 cell line is a widely used pharmacological tool for studying G-protein coupled receptors, including mAChRs. Our results highlight the importance of investigating the longer term fate of these cells in short term signalling studies. Identifying how and why activation of the M1 mAChR signals apoptosis in these cells may lead to a better understanding of how mAChRs regulate cell-fate decisions.

  1. Prehistoric human settling on the Tibetan Plateau

    Science.gov (United States)

    Chen, Fahu; Zhang, Dongju; Dong, Guanghui

    2017-04-01

    When and where did human first settle down on the Tibetan Plateau is under hot debate among archaeologist, anthropologists, geneticist and paleo-geographers. Based on systematic archaeological, chronological and archaeo-botanical studies of 53 sites in Northeastern Tibetan Plateau, we propose that agriculture facilitated human permanent settlement on the Tibetan Plateau initially since 5200 years ago below 2500 masl and since 3600 years ago up to around 4000 masl, possibly assisted by domesticated animals (Chen et al. 2015). By studying hand- and footprints in Chusang, Meyer et al. (2016) argue that hunter-gatherers permanently occupied central Tibetan Plateau in early Holocene without the help of agriculture. However, we think the limited hand- and footprints evidence found in Chusang could indicate no more than prehistoric hunter-gatherers presence on the remote central Tibetan Plateau in the early Holocene. In addition, by reviewing all the published archaeological data, we propose that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in the Northeastern Tibetan Plateau (NETP). This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) when human adapted to the high altitude environment and climate change with different strategies and techniques. Particularly, the prevail of microlithic technology in North China provoked hunter-gatherers' first visit to the NETP in relatively ameliorated last Deglacial period, and the the quick development of millet farming and subsequent mixed barley-wheat farming and sheep herding facilitated farmers and herders permanently settled in Tibetan Plateau, even above 3000 masl, during mid- and late Holocene. References: Chen et al., 2015. Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 BP. Science, 347: 248-250. Meyer et al., 2016

  2. "m=1" coatings for neutron guides

    OpenAIRE

    Cooper-Jensen, C.P.; Vorobiev, A.; Klinkby, Esben Bryndt; Kapaklis, V.; Wilkens, H.; Rats, D.; Hjörvarsson, B.; Kirstein, O.; Bentley, Philip

    2014-01-01

    A substantial part of the price for a neutron guide is the shielding needed because of the gamma ray produced when neutrons are absorbed. This absorption occurs in the coating and the substrate of the neutron guides. Traditional m=1 coatings have been made of Ni and if reflectivity over the critical angle of Ni is needed one has used Ni58 or Ni/Ti multilayer coatings. Ni has one of the highest neutron scattering density but it also has a fairly high absorption cross section for cold and therm...

  3. A Combined Raindrop Aggregate Destruction Test-Settling Tube (RADT-ST Approach to Identify the Settling Velocity of Sediment

    Directory of Open Access Journals (Sweden)

    Liangang Xiao

    2015-10-01

    Full Text Available The use of sediment settling velocity based on mineral grain size distribution in erosion models ignores the effects of aggregation on settling velocity. The alternative approach, wet-sieved aggregate size distribution, on the other hand, cannot represent all destructive processes that eroded soils may experience under impacting raindrops. Therefore, without considering raindrop impact, both methods may lead to biased predictions of the redistribution of sediment and associated substances across landscapes. Rainfall simulation is an effective way to simulate natural raindrop impact under controlled laboratory conditions. However, very few methods have been developed to integrate rainfall simulation with the settling velocity of eroded sediment. This study aims to develop a new proxy, based on rainfall simulation, in order to identify the actual settling velocity distribution of aggregated sediment. A combined Raindrop Aggregate Destruction Test-Settling Tube (RADT-ST approach was developed to (1 simulate aggregate destruction under a series of simulated rainfalls; and (2 measure the actual settling velocity distribution of destroyed aggregates. Mean Weight Settling Velocity (MWSV of aggregates was used to investigate settling behaviors of different soils as rainfall kinetic energy increased. The results show the settling velocity of silt-rich raindrop impacted aggregates is likely to be underestimated by at least six times if based on mineral grain size distribution. The RADT-ST designed in this study effectively captures the effects of aggregation on settling behavior. The settling velocity distribution should be regarded as an evolving, rather than steady state parameter during erosion events. The combined RADT-ST approach is able to generate the quasi-natural sediment under controlled simulated rainfall conditions and is adequately sensitive to measure actual settling velocities of differently aggregated soils. This combined approach provides

  4. Group Settling Velocity of Non-Cohesive Sediment Mixtures

    Institute of Scientific and Technical Information of China (English)

    WU Hualin; SHEN Huanting; ZHU Jianrong; ZHANG Xiaofeng

    2000-01-01

    Settling velocity is a fundamental parameter in sediment transport dynamics. For uniform par-ticles, there are abundant formulas for calculation of their settling velocities. But in natural fields, sediment consists of non-uniform particles. The interaction among particles is complex and should not be neglected. In this paper, based on the analysis of settling mechanism of non-cohesive and non-uniform particles, a theoretical model to describe settling mechanism is proposed. Besides suspension concentration andupward turbulent flow caused by other particles, collision among particles is another main factor influencing settling velocity. By introducing the collision theory, equations of fall velocity before collision, collision probability, and fall velocity after collision are established. Finally, a formula used to calculate the settling velocity of non-cohesive particles with wide grain gradation is presented, which agrees well with the experimental data.

  5. A new settling velocity model to describe secondary sedimentation

    DEFF Research Database (Denmark)

    Ramin, Elham; Wágner, Dorottya Sarolta; Yde, Lars

    2014-01-01

    distribution in SSTs can be predicted using computational fluid dynamics (CFD) tools. Despite extensive studies on the compression settling behaviour of activated sludge and the development of advanced settling velocity models for use in SST simulations, these models are not often used, due to the challenges...... associated with their calibration. In this study, we developed a new settling velocity model, including hindered, transient and compression settling, and showed that it can be calibrated to data from a simple, novel settling column experimental set-up using the Bayesian optimization method DREAM......(ZS). In addition, correlations between the Herschel-Bulkley rheological model parameters and sludge concentration were identified with data from batch rheological experiments. A 2-D axisymmetric CFD model of a circular SST containing the new settling velocity and rheological model was validated with full...

  6. "m=1" coatings for neutron guides

    DEFF Research Database (Denmark)

    Cooper-Jensen, C.P.; Vorobiev, A.; Klinkby, Esben Bryndt

    2014-01-01

    A substantial part of the price for a neutron guide is the shielding needed because of the gamma ray produced when neutrons are absorbed. This absorption occurs in the coating and the substrate of the neutron guides. Traditional m=1 coatings have been made of Ni and if reflectivity over...... the critical angle of Ni is needed one has used Ni58 or Ni/Ti multilayer coatings. Ni has one of the highest neutron scattering density but it also has a fairly high absorption cross section for cold and thermal neutrons and when a neutron is absorbed it emits a lot of gamma rays, some with energies above 9 Me......V. Materials like diamond and Be have higher neutron scattering density than Ni, have smaller absorption cross section and when a neutron is absorbed they emit much less gamma ray and at lower energies. We present results, both theoretically and experimentally, comparing Ni with Be and preliminary results...

  7. Dateline USA: Settling the West, 1800-1900.

    Science.gov (United States)

    Chatton, Barbara; O'Laughlin, Michael

    1998-01-01

    Presents an annotated bibliography of titles related to the theme "Settling the West" which are appropriate for primary, elementary, and middle grades. Topics include overviews of Western history; early 19th century; the gold rush; the pony express; travelers by trail, rail, and ship; settling the West; cowboys and cattle; and the…

  8. Flocculation and Settling Velocity Estimates for Reservoir Sedimentation Analysis

    Science.gov (United States)

    2016-02-01

    1994) and Winterwerp (1998) to describe floc properties based on the principles of fractal geometry. MODELS OF FLOC SETTLING: In practical...2007; Pejrup and Mikkelsen 2010), (5) fractal -based (Winterwerp 1998; Khelifa and Hill 2006; Strom and Keyvani 2011), and (6) Population Balance...Richardson and Zaki 1954). Fractal -Based. Settling velocity models based on fractal theory have recently gained wider application by mathematicians

  9. A new settling velocity model to describe secondary sedimentation.

    Science.gov (United States)

    Ramin, Elham; Wágner, Dorottya S; Yde, Lars; Binning, Philip J; Rasmussen, Michael R; Mikkelsen, Peter Steen; Plósz, Benedek Gy

    2014-12-01

    Secondary settling tanks (SSTs) are the most hydraulically sensitive unit operations in biological wastewater treatment plants. The maximum permissible inflow to the plant depends on the efficiency of SSTs in separating and thickening the activated sludge. The flow conditions and solids distribution in SSTs can be predicted using computational fluid dynamics (CFD) tools. Despite extensive studies on the compression settling behaviour of activated sludge and the development of advanced settling velocity models for use in SST simulations, these models are not often used, due to the challenges associated with their calibration. In this study, we developed a new settling velocity model, including hindered, transient and compression settling, and showed that it can be calibrated to data from a simple, novel settling column experimental set-up using the Bayesian optimization method DREAM(ZS). In addition, correlations between the Herschel-Bulkley rheological model parameters and sludge concentration were identified with data from batch rheological experiments. A 2-D axisymmetric CFD model of a circular SST containing the new settling velocity and rheological model was validated with full-scale measurements. Finally, it was shown that the representation of compression settling in the CFD model can significantly influence the prediction of sludge distribution in the SSTs under dry- and wet-weather flow conditions.

  10. Cancer risks posed by aflatoxin M1.

    Science.gov (United States)

    Hsieh, D P; Cullen, J M; Hsieh, L S; Shao, Y; Ruebner, B H

    1985-01-01

    The suspect milk-borne carcinogen, aflatoxin M1 (AFM), was produced and isolated from the rice culture of the fungus Aspergillus flavus NRRL3251 for confirmation and determination of the potency of its carcinogenicity in the male adult Fischer rat. The carcinogen was mixed into an agar-based, semisynthetic diet at 0, 0.5, 5, and 50 ppb (microgram/kg) and was fed to groups of animals continuously for 19-21 months. Aflatoxin B1 (AFB), of which AFM is a metabolite, at 50 ppb was used as a positive control. Hepatocarcinogenicity of AFM was detected at 50 ppb, but not at 5 or 0.5 ppb, with a potency of 2-10% that of AFB. A low incidence of intestinal adenocarcinomas was found in the AFM 50 ppb group, but not in any other groups. At 0.5 ppb, the action level enforced by the U.S.A. Food and Drug Administration, AFM induced no liver lesions in the rats but stimulated the animals' growth. On the average, the rats in the 0.5 ppb group weighed 11% (p less than 0.001) more than those in the control group. This increased growth was associated with increased feed intake. Based on the biological activity of AFM at the relevant low doses and the estimated level of human exposure to AFM through consumption of milk, the cancer risk posed by this contaminant for human adults is assessed to be very low. For infants, further studies are warranted because milk constitutes the major ingredient of the infant diet and because infant animals have been shown to be more sensitive to the carcinogenicity of AFB than adult animals.

  11. Coral larvae settle at a higher frequency on red surfaces

    Science.gov (United States)

    Mason, B.; Beard, M.; Miller, M. W.

    2011-09-01

    Although chemical cues serve as the primary determinants of larval settlement and metamorphosis, light is also known to influence the behavior and the settlement of coral planulae. For example, Porites astreoides planulae settle preferentially on unconditioned red substrata. In order to test whether this behavior was a response to color and whether other species also demonstrate color preference, settlement choice experiments were conducted with P. astreoides and Acropora palmata. In these experiments, larvae were offered various types of plastic substrata representing three to seven different color choices. Both species consistently settled on red (or red and orange) substrata at a higher frequency than other colors. In one experiment, P. astreoides settled on 100% of red, plastic cable ties but failed to settle on green or white substrata. In a second experiment, 24% of larvae settled on red buttons, more than settled on six other colors combined. A. palmata settled on 80% of red and of orange cables ties but failed to settle on blue in one experiment and settled on a greater proportion of red acrylic squares than on four other colors or limestone controls in a second experiment. The consistency of the response across a variety of plastic materials suggests the response is related to long-wavelength photosensitivity. Fluorescence and reflectance spectra of experimental substrata demonstrated that the preferred substrata had spectra dominated by wavelengths greater than 550 nm with little or no reflection or emission of shorter wavelengths. These results suggest that some species of coral larvae may use spectral cues for fine-scale habitat selection during settlement. This behavior may be an adaptation to promote settlement in crustose coralline algae (CCA)-dominated habitats facilitating juvenile survival.

  12. Settling of an asymmetric dumbbell in a quiescent fluid

    CERN Document Server

    Candelier, F

    2015-01-01

    We compute the hydrodynamic torque on a dumbbell (two spheres linked by a massless rigid rod) settling in a quiescent fluid at small but finite Reynolds number. The spheres have the same mass densities but different sizes. When the sizes are quite different the dumbbell settles vertically, the largest sphere first. But when the size difference is sufficiently small then its steady-state angle is determined by a competition between the size difference and the Reynolds number. When the sizes of the spheres are exactly equal we recover a result derived by Khayat & Cox (1989) for slender bodies: the dumbbell settles horizontally owing to fluid inertia effects.

  13. Magma mixing induced by particle settling

    Science.gov (United States)

    Renggli, Christian J.; Wiesmaier, Sebastian; De Campos, Cristina P.; Hess, Kai-Uwe; Dingwell, Donald B.

    2016-11-01

    A time series of experiments at high temperature have been performed to investigate the influence of particle settling on magma mixing. A natural rhyolite glass was held above a natural basalt glass in a platinum crucible. After melting of the glasses at superliquidus temperatures, a platinum sphere was placed on the upper surface of the rhyolitic melt and sank into the experimental column (rhyolitic melt above basaltic melt). Upon falling through the rhyolitic-basaltic melt interface, the Pt sphere entrained a filament of rhyolitic melt in its further fall. The quenched products of the experiments were imaged using X-ray microCT methods. The images of our time series of experiments document the formation of a rhyolite filament as it is entrained into the underlying basalt by the falling platinum sphere. When the Pt particle reached the bottom of the crucible, the entrained rhyolitic filament started to ascend buoyantly up to the initial rhyolitic-basaltic interface. This generated a significant thickness increase of a comingled "melange" layer at the interface due to "liquid rope coiling" and piling up of the filament. As a consequence, the basalt/rhyolite interface was greatly enlarged and diffusive hybridisation greatly accelerated. Further, bubbles, originating at the interface, are observed to have risen into the overlying rhyolite dragging basalt filaments with them. Upon crossing the basalt/rhyolite interface, the bubbles have non-spherical shapes as they adapt to the differing surface tensions of basaltic and rhyolitic melts. Major element profiles, measured across the rhyolite filaments, exhibit asymmetrical shapes from the rhyolite into the basalt. Na and Ti reveal uphill diffusion from the rhyolite towards the interface in the filament cross sections. These results reveal the potential qualitative complexity of the mingling process between rhyolitic and basaltic magmas in the presence of sinking crystals. They imply that crystal-rich magma mingling may

  14. Effects of physical variables on settling velocities of calcium and ...

    African Journals Online (AJOL)

    ADOWIE PERE

    study, series of bench-scale batch-wise precipitation and settling tests were performed to ... Iboroma, (2015) had reported that solid phase .... appearance of a white less-dense gelatinous ... suspension boundary were indicative of high particle.

  15. Batch settling curve registration via image data modeling.

    Science.gov (United States)

    Derlon, Nicolas; Thürlimann, Christian; Dürrenmatt, David; Villez, Kris

    2017-05-01

    To this day, obtaining reliable characterization of sludge settling properties remains a challenging and time-consuming task. Without such assessments however, optimal design and operation of secondary settling tanks is challenging and conservative approaches will remain necessary. With this study, we show that automated sludge blanket height registration and zone settling velocity estimation is possible thanks to analysis of images taken during batch settling experiments. The experimental setup is particularly interesting for practical applications as it consists of off-the-shelf components only, no moving parts are required, and the software is released publicly. Furthermore, the proposed multivariate shape constrained spline model for image analysis appears to be a promising method for reliable sludge blanket height profile registration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. THE MILLER OPERATIONAL AMPLIFIER’S SETTLING RESPONSE

    Directory of Open Access Journals (Sweden)

    E. Ruíz-May

    2007-08-01

    Full Text Available This paper presents a third-order transfer function to model the settling response of the Miller operationalamplifier. The amplifier was simulated (spice and designed according to design rules of a standard 1.5μmCMOS fabrication process. The proposed mathematical model -based on design parameters under thedesigner’s control- is the best settling approach reported up to now

  17. A new settling velocity model to describe secondary sedimentation

    DEFF Research Database (Denmark)

    Ramin, Elham; Wágner, Dorottya Sarolta; Yde, Lars

    2014-01-01

    Secondary settling tanks (SSTs) are the most hydraulically sensitive unit operations in biological wastewater treatment plants. The maximum permissible inflow to the plant depends on the efficiency of SSTs in separating and thickening the activated sludge. The flow conditions and solids distribut......Secondary settling tanks (SSTs) are the most hydraulically sensitive unit operations in biological wastewater treatment plants. The maximum permissible inflow to the plant depends on the efficiency of SSTs in separating and thickening the activated sludge. The flow conditions and solids...... associated with their calibration. In this study, we developed a new settling velocity model, including hindered, transient and compression settling, and showed that it can be calibrated to data from a simple, novel settling column experimental set-up using the Bayesian optimization method DREAM......(ZS). In addition, correlations between the Herschel-Bulkley rheological model parameters and sludge concentration were identified with data from batch rheological experiments. A 2-D axisymmetric CFD model of a circular SST containing the new settling velocity and rheological model was validated with full...

  18. Aggregation and settling in aqueous polydisperse alumina nanoparticle suspensions

    CERN Document Server

    Witharana, Sanjeeva; Xu, Dan; Lai, Xiaojun; Ding, Yulong

    2012-01-01

    Nanoparticle suspensions (also called nanofluids) are often polydisperse and tend to settle with time. Settling kinetics in these systems are known to be complex and hence challenging to understand. In this work, polydisperse spherical alumina (Al2O3) nanoparticles in the size range of ~10-100nm were dispersed in water and examined for aggregation and settling behaviour near its isoelectric point (IEP). A series of settling experiments were conducted and the results were analysed by photography and by Small Angle X-ray Scattering (SAXS). The settling curve obtained from standard bed height measurement experiments indicated two different types of behaviour, both of which were also seen in the SAXS data. But the SAXS data were remarkably able to pick out the rapid settling regime as a result of the high temporal resolution (10s) used. By monitoring the SAXS intensity, it was further possible to record the particle aggregation process for the first time. Optical microscopy images were produced on drying and drie...

  19. On the nonexistence of $[\\binom{2m}{m-1}, 2m, \\binom{2m-1}{m-1}]$, $m$ odd, complex orthogonal design

    CERN Document Server

    Li, Yuan

    2011-01-01

    Complex orthogonal designs (CODs) are used to construct space-time block codes. COD $\\mathcal{O}_z$ with parameter $[p, n, k]$ is a $p\\times n$ matrix, where nonzero entries are filled by $\\pm z_i$ or $\\pm z^*_i$, $i = 1, 2,..., k$, such that $\\mathcal{O}^H_z \\mathcal{O}_z = (|z_1|^2+|z_2|^2+...+|z_k|^2)I_{n \\times n}$. Adams et al. in "The final case of the decoding delay problem for maximum rate complex orthogonal designs," IEEE Trans. Inf. Theory, vol. 56, no. 1, pp. 103-122, Jan. 2010, first proved the nonexistence of $[\\binom{2m}{m-1}, 2m, \\binom{2m-1}{m-1}]$, $m$ odd, COD. Combining with the previous result that decoding delay should be an integer multiple of $\\binom{2m}{m-1}$, they solved the final case $n \\equiv 2 \\pmod 4$ of the decoding delay problem for maximum rate complex orthogonal designs. In this paper, we give another proof of the nonexistence of COD with parameter $[\\binom{2m}{m-1}, 2m, \\binom{2m-1}{m-1}]$, $m$ odd. Our new proof is based on the uniqueness of $[\\binom{2m}{m-1}, 2m-1, \\binom{...

  20. Settling decisions and heterospecific social information use in shrikes.

    Directory of Open Access Journals (Sweden)

    Martin Hromada

    Full Text Available Animals often settle near competitors, a behavior known as social attraction, which belies standard habitat selection theory. Two hypotheses account for these observations: individuals obtain Allee benefits mediated by the physical presence of a competitor, or they use successfully settled individual as a source of information indicating the location of high quality habitat. We evaluated these hypotheses experimentally in two species of shrikes. These passerine birds with a raptor-like mode of life impale prey to create larders that serve as an indicator of male/habitat quality. Thus, two forms of indirect information are available in our system: a successfully settled shrike and its larder. Typically these two cues are associated with each other, however, our experimental treatment created an unnatural situation by disassociating them. We manipulated the presence of larders of great grey shrikes and examined the settling decisions of red-backed shrikes within and outside the great grey shrike territories. Male red-backed shrikes did not settle sooner on plots with great grey shrikes compared to plots that only contained artificial larders indicating that red-backed shrikes do not use the physical presence of a great grey shrike when making settling decisions which is inconsistent with the Allee effect hypothesis. In contrast, for all plots without great grey shrikes, red-backed shrikes settled, paired and laid clutches sooner on plots with larders compared to plots without larders. We conclude that red-backed shrikes use larders of great grey shrikes as a cue to rapidly assess habitat quality.

  1. LAMINAR SETTLING OF GLASS BEADS IN VISCO-PLASTIC LIQUIDS

    Directory of Open Access Journals (Sweden)

    Mikoláš Kesely

    2016-04-01

    Full Text Available The paper deals with a determination of the terminal settling velocity of coarse particles in quiescent visco-plastic liquids of Herschel-Bulkley type. Experiments on laminar settling of glass beads of different sizes were conducted in transparent Carbopol solutions of various rheological properties in a sedimentation column. The terminal settling velocity of a solitude bead was determined together with the rheological parameters of the Carbopol liquid. An evaluation of the experimental results confirms the existence of the laminar regime for all tests and compares the measured velocities with predictions by Wilson et al. method. Furthermore, an alternative method is proposed for a prediction of the terminal settling velocity in the laminar regime which uses a particle-based determination of the strain rate in the expression for the equivalent viscosity. A comparison with our experimental results shows that the predictions using the proposed method agree well with the experiments and the proposed method is in the laminar settling regime more accurate than the Wilson et al. method.

  2. Optimizing settling conditions for treatment of liquid hog manure.

    Science.gov (United States)

    Trias, M; Mortula, M M; Hu, Z; Gagnon, G A

    2004-08-01

    Sedimentation is a widely used separation method for treating agricultural waste. There are several chemical and biological characteristics, which can affect the settling behavior and liquid waste. The optimization of cation balances and potential for nitrification are among these processes. In addition to sedimentation, it can also affect the dewaterability of the samples. Liquid hog manure was used during the laboratory based experiments to investigate the effects of Ca2+ and Mg2+ ions and nitrification inhibition on the overall settling and dewatering characteristics. The results indicated that settling and dewatering characteristics improved during the course of the experiments. However, the improvement in settling and dewatering characteristics was inconsistent and not statistically significant. Cation addition in aerated reactor increased the highest settling velocity (94%). The improvement in dewaterability, as quantified by capillary suction time, was also not consistent. The greatest filterability observed in the supernatant was a capillary suction time of 40 s for a M:D ratio of 2:1. Initial NH 4 + concentration was more important than the nitrification inhibitor, as the presence of nitrification inhibitor increased the nitrification rate by over 300% because of the high initial NH 4 + concentration and low volatile suspended solid. The results from these experiments provide the basis for further field evaluation of cation optimization.

  3. Characterization of Settled Atmospheric Dust by the DART Experiment

    Science.gov (United States)

    Landis, Geoffrey A.; Jenkins, Phillip P.; Baraona, Cosmo

    1999-01-01

    The DART ("Dust Accumulation and Removal Test") package is an experiment which will fly as part of the MIP experiment on the Mars-2001 Surveyor Lander. Dust deposition could be a significant problem for photovoltaic array operation for long duration emissions on the surface of Mars. Measurements made by Pathfinder showed 0.3% loss of solar array performance per day due to dust obscuration. The DART experiment is designed to quantify dust deposition from the Mars atmosphere, measure the properties of settled dust, measure the effect of dust deposition on the array performance, and test several methods of mitigating the effect of settled dust on a solar array. Although the purpose of DART (along with its sister experiment, MATE) is to gather information critical to the design of future power systems on the surface of Mars, the dust characterization instrumentation on DART will also provide significant scientific data on the properties of settled atmospheric dust.

  4. Settling of a cylindrical particle in a stagnant fluid

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Rosendahl, Lasse; Yin, Chungen

    2007-01-01

    on their motion. In total 66 experiments were carried out with a particle Reynolds number in the range between 2000 and 15000. All experiments show a distinct oscillation around one of the particle minor axes. For all experiments the oscillating velocity is compared to the mean settling velocity, and it is found......The objective of this work is to collect data and develop models for cylindrical particles which could be used in numerical multiphase flow modeling. Trajectories of cylindrical particles settling in stagnant water are filmed from two directions in order to derive detailed information...... that the oscillating velocity increases with increasing mean settling velocity. Based on the experiment new expressions for drag and lift coefficient are proposed....

  5. An Analysis of Nanoparticle Settling Times in Liquids

    CERN Document Server

    Liyanage, D D; Kumbalatara, A A K; Weliwita, J A; Witharana, S

    2016-01-01

    Aggregation and settling are crucial phenomena that involve particulate systems. For particle sizes of millimetre and above, there are reasonable accurate predicting tools. However for smaller particle sizes, there appears to be a void in knowledge. This paper presents an analytical model to predict the settling rates of nano-to-micro size particulate systems. The model was developed as a combination of modified classical equations and graphical methods. A calculation sequence also is presented. By validation with available experimental data for settling nano-to-micro systems, it was found that the two schemes show order of magnitude agreement. A significant feature of this model is its ability to accommodate non-spherical particles and different fractal dimensions.

  6. Settling-velocity specific SOC distribution on hillslopes

    Science.gov (United States)

    Hu, Yaxian; Asefaw Berhe, Asmeret; Fogel, Marilyn L.; Heckrath, Goswin J.; Kuhn, Nikolaus J.

    2016-04-01

    The net effect of soil erosion by water, as a sink or source of atmospheric CO2, is determined by the spatial (re-)distribution and stability of eroded soil organic carbon (SOC). The depositional position of eroded SOC is a function of the transport distances of soil fractions where the SOC is stored. In theory, the transport distances of soil fractions are related to their settling velocities under given flow conditions. Yet, very few field investigations have been conducted to examine the actual movement of eroded soil fractions along hillslopes, let alone the re-distribution pattern of SOC fractions. Eroding sandy soils and sediment were sampled after a series of rainfall events along a slope on a freshly seeded cropland in Jutland, Denmark. All the soil samples were fractionated into five settling classes using a settling tube apparatus. The spatial distribution of soil settling classes shows a coarsening effect immediately below the eroding slope, followed by a fining trend at the slope tail. The δ13C values of soil fractions were more positive at the footslope than on the slope shoulder or at the slope tail, suggesting enhanced decomposition rate of fresh SOC input at the footslope during or after erosion-induced transport. Overall, our results illustrate that immediate deposition of fast settling soil fractions and the associated SOC at footslopes must be appropriately accounted for in attempts to quantify the role of soil erosion in terrestrial carbon sequestration. A SOC erodibility parameter based on actual settling velocity distribution of eroded fractions is needed to better calibrate soil erosion models.

  7. Swarms of particles settling under gravity in a viscous fluid

    CERN Document Server

    Ekiel-Jezewska, Maria L

    2012-01-01

    We investigate swarms made of a small number of particles settling under gravity in a viscous fluid. The particles do not touch each other and can move relative to each other. The dynamics is analyzed in the point-particle approximation. A family of swarms is found with periodic oscillations of all the settling particles. In the presence of an additional particle above the swarm, the trajectories are horizontally repelled from the symmetry axis, and flattened vertically. The results are used to explain how a spherical cloud, made of a large number of particles distributed at random, evolves and destabilizes.

  8. A Method for Measuring Sludge Settling Characteristics in Turbulent Flows

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Larsen, Torben

    1996-01-01

    distribution occurs in the middle of the column. This eliminates time scale effects such as flocculation from the measurements, as the resulting settling velocity only can be found at steady state and uniform conditions. The method assumes that flocculated sludge settles faster than disintegratedsludge to make...... can be measured at arbitrarily selected combinations of turbulence and concentration. The foremost advantage of the method is that settlilng characteristics measured in this way can be utilized directly in numerical models of sedimentation tanks, process tanks, etc....

  9. Measuring and modeling the magnetic settling of superparamagnetic nanoparticle dispersions.

    Science.gov (United States)

    Prigiobbe, Valentina; Ko, Saebom; Huh, Chun; Bryant, Steven L

    2015-06-01

    In this paper, we present settling experiments and mathematical modeling to study the magnetic separation of superparamagnetic iron-oxide nanoparticles (SPIONs) from a brine. The experiments were performed using SPIONs suspensions of concentration between 3 and 202g/L dispersed in water and separated from the liquid under the effect of a permanent magnet. A 1D model was developed in the framework of the sedimentation theory with a conservation law for SPIONs and a mass flux function based on the Newton's law for motion in a magnetic field. The model describes both the hindering effect of suspension concentration (n) during settling due to particle collisions and the increase in settling rate due to the attraction of the SPIONs towards the magnet. The flux function was derived from the settling experiments and the numerical model validated against the analytical solution and the experimental data. Suspensions of SPIONs were of 2.8cm initial height, placed on a magnet, and monitored continuously with a digital camera. Applying a magnetic field of 0.5T of polarization, the SPION's velocity was of approximately 3·10(-5)m/s close to the magnet and decreases of two orders of magnitude across the domain. The process was characterized initially by a classical sedimentation behavior, i.e., an upper interface between the clear water and the suspension slowly moving towards the magnet and a lower interface between the sediment layer and the suspension moving away from the magnet. Subsequently, a rapid separation of nanoparticle occured suggesting a non-classical settling phenomenon induced by magnetic forces which favor particle aggregation and therefore faster settling. The rate of settling decreased with n and an optimal condition for fast separation was found for an initial n of 120g/L. The model agrees well with the measurements in the early stage of the settling, but it fails to describe the upper interface movement during the later stage, probably because of particle

  10. The conformation of acetylated virginiamycin M1 and virginiamycin M1 in explicit solvents.

    Science.gov (United States)

    Ng, Chai Ann; Zhao, Wen; Dang, Jason; Bergdahl, Mikael; Separovic, Frances; Brownlee, Robert T C; Metzger, Robert P

    2007-05-01

    The three-dimensional structure of acetylated virginiamycin M(1) (acetylated VM1) in chloroform and in a water/acetonitrile mixture (83:17 v/v) have been established through 2D high resolution NMR experiments and molecular dynamics modeling and the results compared with the conformation of the antibiotic VM1 in the same and other solvents. The results indicated that acetylation of the C-14 OH group of VM1 caused it to rotate about 90 degrees from the position it assumed in non-acetylated VM1. The conformation of both VM1 and acetylated VM1 appear to flatten in moving from a nonpolar to polar solvent. However, the acetylated form has a more hydrophobic nature. The acetylated VM1 in chloroform and in water/acetonitrile solution had a similar configuration to that of VM1 bound to 50S ribosomes and to the Vat(D) active sites as previously determined by X-ray crystallography. Docking studies of VM1 to the 50S ribosomal binding site and the Vat(D) gave conformations very similar to those derived from X-ray crystallographic studies. The docking studies with acetylated VM1 suggested the possibility of a hydrogen bond from the acetyl carbonyl group oxygen of acetylated VM1 to the 2' hydroxyl group of ribose of adenosine 2538 at the ribosomal VM1 binding site. No hydrogen bonds between acetylated VM1 and the Vat(D) active sites were found; the loss of this binding interaction partly accounts for the release of the product from the active site.

  11. Improving Settling Dynamics of Activated Sludge by Adding Fine Talc Powder

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Larsen, Torben; Clauss, F.

    1996-01-01

    . The settling velocity was measured with a recirculated settling column under different concentrations and turbulence levels. Numerical simulation of a secondary settling tank indicates that adding fine powder will improve the overall performance considerably.......The effect of adding varying mixtures of talc and chlorite powder to activated sludge in order to improve the settling characteristic has been studied. The powder is found to improve the settling velocity of the sludge, strictly by increasing the average density of the sludge floc aggregate...

  12. Qualification Lab Testing on M1 Abrams Engine Oil Filters

    Science.gov (United States)

    2016-11-01

    UNCLASSIFIED QUALIFICATION LAB TESTING ON M1 ABRAMS ENGINE OIL FILTERS FINAL REPORT TFLRF No. 483 by Kristi K. Rutta U.S...the originator. UNCLASSIFIED QUALIFICATION LAB TESTING ON M1 ABRAMS ENGINE OIL FILTERS FINAL REPORT TFLRF No. 483 by Kristi K...TITLE AND SUBTITLE Qualification Lab Testing on M1 Abrams Engine Oil Filter 5a. CONTRACT NUMBER W56HZV-15-C-0030 5b. GRANT NUMBER 5c. PROGRAM

  13. Develop Efficient Leak Proof M1 Abrams Plenum Seal

    Science.gov (United States)

    2014-05-07

    UNCLASSIFIED UNCLASSIFIED ER-GLSV11389-001.docx Develop Efficient Leak Proof M1 Abrams Plenum Seal SBIR Phase I: Topic A13-061...Leak Proof M1 Abrams Plenum Seal Christian Muehfeld Steve Pennala Great Lakes Sound & Vibration, Inc. 47140 North Main Street Houghton, MI 49931 ER...061. The purpose of this report is to show the feasibility of developing an efficient, leak proof plenum seal for the M1 Abrams . It also shows the

  14. 39 CFR 955.14 - Settling the record.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Settling the record. 955.14 Section 955.14 Postal Service UNITED STATES POSTAL SERVICE PROCEDURES RULES OF PRACTICE BEFORE THE POSTAL SERVICE BOARD OF... appeal. (d) The Board may consider the Federal Rules of Evidence for guidance regarding admissibility of...

  15. SVOC partitioning between the gas phase and settled dust indoors

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Nazaroff, W. W.

    2010-01-01

    Semivolatile organic compounds (SVOCs) are a major class of indoor pollutants. Understanding SVOC partitioning between the gas phase and settled dust is important for characterizing the fate of these species indoors and the pathways by which humans are exposed to them. Such knowledge also helps...

  16. Three Major Aerospace Industrial Projects Settled In Xi'an

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Three major aerospace industrial projects settled in Xi'an National Civil Aerospace Industrial Base and the signing ceremonywas held on August 13. The settlement of the 3 projects will promote the development of space science and technologyindustry and the local economy while speeding up the construction of Xi'an National Civil Aerospace Industrial Base.

  17. Connecticut Power Company Settles with EPA for Transformer Spill

    Science.gov (United States)

    The Connecticut Light and Power Company has agreed to pay $47,000 to settle claims by the US Environmental Protection Agency that it violated federal regulations in its management of a transformer that spilled 50 gallons of oil containing PCBs at a locatio

  18. Clifford Sifton, Immigration and the Settling of the West.

    Science.gov (United States)

    Bennett, Paul W.

    1985-01-01

    Clifford Sifton stands out in most Canadian history texts as the architect of the immigration policy that settled the prairies West and shaped the development of modern Canada. Background information on Sifton is provided. Letters Sifton wrote regarding immigration policy are analyzed. (RM)

  19. Numerical Modelling and Measurement in a Test Secondary Settling Tank

    DEFF Research Database (Denmark)

    Dahl, C.; Larsen, Torben; Petersen, O.

    1994-01-01

    A numerical model and measurements of flow and settling in activated sludge suspension is presented. The numerical model is an attempt to describe the complex and interrelated hydraulic and sedimentation phenomena by describing the turbulent flow field and the transport/dispersion of suspended sl...

  20. First Year Mathematics Undergraduates' Settled Images of Tangent Line

    Science.gov (United States)

    Biza, Irene; Zachariades, Theodossios

    2010-01-01

    This study concerns 182 first year mathematics undergraduates' perspectives on the tangent line of function graph in the light of a previous study on Year 12 pupils' perspectives. The aim was the investigation of tangency images that settle after undergraduates' distancing from the notion for a few months and after their participation in…

  1. Nonmonotonic settling of a sphere in a cornstarch suspension

    NARCIS (Netherlands)

    von Kann, S.; von Kann, Stefan; Snoeijer, Jacobus Hendrikus; Lohse, Detlef; van der Meer, Roger M.

    2011-01-01

    Cornstarch suspensions exhibit remarkable behavior. Here, we present two unexpected observations for a sphere settling in such a suspension: In the bulk of the liquid the velocity of the sphere oscillates around a terminal value, without damping. Near the bottom the sphere comes to a full stop, but

  2. 37 CFR 10.67 - Settling similar claims of clients.

    Science.gov (United States)

    2010-07-01

    ... clients. 10.67 Section 10.67 Patents, Trademarks, and Copyrights UNITED STATES PATENT AND TRADEMARK OFFICE... Office Code of Professional Responsibility § 10.67 Settling similar claims of clients. A practitioner who represents two or more clients shall not make or participate in the making of an aggregate settlement of the...

  3. Study on dealkalization and settling performance of red mud.

    Science.gov (United States)

    Luo, Muxi; Qi, Xuejiao; Zhang, Yurui; Ren, Yufei; Tong, Jiacheng; Chen, Zining; Hou, Yiming; Yeerkebai, Nuerxiate; Wang, Hongtao; Feng, Shijin; Li, Fengting

    2017-01-01

    At present, the dealkalization and comprehensive utilization of red mud is a worldwide problem. Studies on the settling performance and phase transformation of red mud by HCl, CaO, and H2O leaching are limited. In this study, the characteristics of red mud were systematically analyzed. The average sizes of graded and initial red mud were 4.11 and 9.20 μm, respectively. X-ray diffraction (XRD), X-ray fluorescence spectra (XRF), and thermogravimetry-differential scanning calorimetry (TG-DSC) results indicated the different mineralogical phases, composition, and thermal behavior. The addition of HCl could neutralize the alkalization in the red mud slurry, and CaO could replace the Na and K. Notably, the pH of the red mud slurry had no obvious change with the increase in water washing times in a certain pH. Interestingly, soluble Al and Fe were not detected in the HCl-red mud and CaO-red mud. In addition, the settling ratio was used to express the settling performance of the red mud slurry. Their interaction mechanisms were proposed, which may include phase transformation and the changing of the size and surface area. The research provided a better understanding of the phase transformation and settling performance in the treatment of red mud by HCl, CaO, and H2O leaching.

  4. Settling of a cylindrical particle in a stagnant fluid

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Rosendahl, Lasse; Yin, Chungen;

    2007-01-01

    The objective of this work is to collect data and develop models for cylindrical particles which could be used in numerical multiphase flow modeling. Trajectories of cylindrical particles settling in stagnant water are filmed from two directions in order to derive detailed information on their mo...

  5. Settling velocity of marine microplastic particles: laboratory tests

    Science.gov (United States)

    Isachenko, Igor; Khatmullina, Lilia; Chubarenko, Irina; Stepanova, Natalia

    2016-04-01

    An assessment of the settling velocity of different classes of microplastic particles (microplastic particles is usually outside the Stokes range (Re 105). Even for such transitional regime, the settling velocity of the particles that could be treated as more or less smooth spheres can be predicted with high accuracy by relationships available in publications. This is not the case for the non-spherical particles like fibres or flakes. There are quite a large number of quasi-theoretical or semi-empirical approaches that take into account the shape and roughness of the particles, usually in the applications to transport of natural sediments. Some engineering formulas for the settling velocity are also developed which have simpler structure along with high degree of accuracy on the set of experimental data. For marine microplastic particles, the absence of relationship between the settling velocity and the properties of the particle requires testing on the samples of marine microplastics. Besides small fragments of rigid plastic (granules, microbeads), there are also fibres and thin plastic sheets (flakes) with some degree of flexibility. The applicability of available formulae to thin and/or flexible plastic particles again requires verification by experiments. The set of laboratory experiments on settling of microplastic particles of various shapes and excess densities in homogeneous water is reported. The particles were collected in water column, bottom sediments and on the beaches of the South-Eastern Baltic. The experiments demonstrate not just different regimes of motion but different manner of the sinking of spheres, flakes and fibres. The very definition of the "settling velocity" has a specific meaning for every kind of a particle shape. The results of test measurements are compared with predictions by several published semi-empirical formulae. We conclude that there are several new questions to discuss in this regard: (i) proper definition of the meaning of

  6. Aggregate Settling Velocities in San Francisco Estuary Margins

    Science.gov (United States)

    Allen, R. M.; Stacey, M. T.; Variano, E. A.

    2015-12-01

    One way that humans impact aquatic ecosystems is by adding nutrients and contaminants, which can propagate up the food web and cause blooms and die-offs, respectively. Often, these chemicals are attached to fine sediments, and thus where sediments go, so do these anthropogenic influences. Vertical motion of sediments is important for sinking and burial, and also for indirect effects on horizontal transport. The dynamics of sinking sediment (often in aggregates) are complex, thus we need field data to test and validate existing models. San Francisco Bay is well studied and is often used as a test case for new measurement and model techniques (Barnard et al. 2013). Settling velocities for aggregates vary between 4*10-5 to 1.6*10-2 m/s along the estuary backbone (Manning and Schoellhamer 2013). Model results from South San Francisco Bay shoals suggest two populations of settling particles, one fast (ws of 9 to 5.8*10-4 m/s) and one slow (ws of Brand et al. 2015). While the open waters of San Francisco Bay and other estuaries are well studied and modeled, sediment and contaminants often originate from the margin regions, and the margins remain poorly characterized. We conducted a 24 hour field experiment in a channel slough of South San Francisco Bay, and measured settling velocity, turbulence and flow, and suspended sediment concentration. At this margin location, we found average settling velocities of 4-5*10-5 m/s, and saw settling velocities decrease with decreasing suspended sediment concentration. These results are consistent with, though at the low end of, those seen along the estuary center, and they suggest that the two population model that has been successful along the shoals may also apply in the margins.

  7. Seasonal variation of polychlorinated biphenyl congeners in surficial sediment, trapped settling material, and suspended particulate material in Lake Michigan, USA.

    Science.gov (United States)

    Robinson, Sander D; Landrum, Peter F; Van Hoof, Patricia L; Eadie, Brian J

    2008-02-01

    A unique time series of surface sediment, trapped settling material, and suspended particulate material polychlorinated biphenyl (PCB) samples were collected at a 45-m deep site off Grand Haven (MI, USA) over a 14-month period. Both concentrations and congener distributions remained constant for the sediments, although there were seasonal and interannual variability in the other matrices. Trapped settling material and suspended particulate material PCB concentrations were substantially lower (~50%) in 1997 than in the samples from December 1997 through July 1998. The cause could not be determined from the data collected, but there were some very large storms during the winter-spring period of 1998, resulting in major sediment resuspension throughout the southern basin. Observed seasonal variation in PCB concentration and congener distribution on particles likely was due to the changes in particle composition. These include particle size and the source of particles (such as the amount of resuspended sediment in trapped settling material), and the role of diagenesis of the organic matter on particles.

  8. Genomic Characterization of Campylobacter jejuni strain M1

    DEFF Research Database (Denmark)

    Friis, Carsten; Wassenaar, Gertrude Maria; Javed, Muhammad A.

    2010-01-01

    publicly available. Compared to these, M1 is closest to strain 81116. Based on the 13 genome sequences, we have identified the C. jejuni pan-genome, as well as the core genome, the auxiliary genes, and genes unique between strains M1 and 81116. The pan-genome contains 2,427 gene families, whilst the core...

  9. FoxM1 Regulates Mammary Luminal Cell Fate

    Directory of Open Access Journals (Sweden)

    Janai R. Carr

    2012-06-01

    Full Text Available Elevated expression of FoxM1 in breast cancer correlates with an undifferentiated tumor phenotype and a negative clinical outcome. However, a role for FoxM1 in regulating mammary differentiation was not known. Here, we identify another function of FoxM1, the ability to act as a transcriptional repressor, which plays an important role in regulating the differentiation of luminal epithelial progenitors. Regeneration of mammary glands with elevated levels of FoxM1 leads to aberrant ductal morphology and expansion of the luminal progenitor pool. Conversely, knockdown of FoxM1 results in a shift toward the differentiated state. FoxM1 mediates these effects by repressing the key regulator of luminal differentiation, GATA-3. Through association with DNMT3b, FoxM1 promotes methylation of the GATA-3 promoter in an Rb-dependent manner. This study identifies FoxM1 as a critical regulator of mammary differentiation with significant implications for the development of aggressive breast cancers.

  10. Nonlinear Propagation of Sound in Recently Settled Flocculated Sediments

    Science.gov (United States)

    Reed, A. H.; Sanders, W. M.

    2016-12-01

    Cohesive sediments undergo changes in a whirlwind. Dumped out of the river and into the estuary, they get bathed in salty water and subject to turbulent motion. During this sequence of events, the clay particles form clay aggregates of larger size with higher settling rates than the clay particles. Once the flocs have settled, cohesive sediments may form a sediment deposit of mud. Our interest is in the factors that control the development of soundspeed within these muds. This paper addresses organic matter influences on floc aggregation and settling rates. In laboratory studies, organic matter type differed in mixtures with either bentonite or kaolinite clays. The organic matter types used were guar gum, a net positive biopolymer, and xanthan gum, a net negative biopolymer derived from bacterial exudates, similar to those commonly found in estuaries. These biopolymers were dissolved into low salinity water (0-10 ppt). The biopolymer mixture was degassed and during the degassing process, either bentonite or kaolinite clay was added to the vessel. Surprisingly, different settling rates occurred in the clay-biopolymer mixtures. The settling rates of the clay-guar mixtures was more rapid (1-2 days) than the settling rate for the clay-xanthan mixtures. While clay-guar consolidated further, clay-xanthan maintained consistency for more than 2 weeks with density slowly increasing during that period. Compressional soundspeed (Vp) measurements were made with depth through the vessel using 0.5 mHz piezoelectric transducers. It was found that Vp in water was similar to that of the clay-xanthan. Vp was the same in the upper 6 cm of mud as it was in the overlying water and Vp decreased to become slower with increasing depth. Compressional wave velocity (Vp) also changed slightly with the guar complexes below the sediment water interface to the depth of the vessel. Vp was slightly slower in the mud than in the water column. Vp of the water was 1480-1495 m/s whereas Vp within the

  11. On (2m + 1)-variable symmetric Boolean functions with submaximum algebraic immunity 2m-1

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    All (2m +1)-variable symmetric Boolean functions with submaximal algebraic immunity 2m-1 are described and constructed. The total number of such Boolean functions is 32 ·22m-3 +3m-2 · 24 - 2 for m≥2.

  12. Relative importance of secondary settling tank models in WWTP simulations

    DEFF Research Database (Denmark)

    Ramin, Elham; Flores-Alsina, Xavier; Sin, Gürkan

    2012-01-01

    Results obtained in a study using the Benchmark Simulation Model No. 1 (BSM1) show that a one-dimensional secondary settling tank (1-D SST) model structure and its parameters are among the most significant sources of uncertainty in wastewater treatment plant (WWTP) simulations [Ramin et al., 2011......]. The sensitivity results consistently indicate that the prediction of sludge production is most sensitive to the variation of the settling parameters. In the present study, we use the Benchmark Simulation Model No. 2 (BSM2), a plant-wide benchmark, that combines the Activated Sludge Model No. 1 (ASM1......) with the Anaerobic Digestion Model No. 1 (ADM1). We use BSM2 as a vehicle to compare two different 1-D SST models, and to assess the relative significance of their performance on WWTP simulation model outputs. The two 1-D SST models assessed include the firstorder model by Takács et al. [1991] and the second...

  13. The nature of particulate organic matter settled on solid substrata

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, M.O.; Wagh, A.B.

    of the particulate material recovered from these two surfaces. Highly significant correlations were observed between the bacterial numbers and the measured parameters. This probably suggests that bacteria were the major source of the particulate matter settled... immerges dans un estuaire a ete analysce: bacteries, chlorophylle a, poids sec, matiere organique, carbone organique, azote, proteines, glueides et lipides. Aucune difference n'a etc dccelee dans lacomposition de la matiere organique et dans les...

  14. Diffusion and Settling in Ap/Bp Stars

    CERN Document Server

    Turcotte, S

    2003-01-01

    Ap/Bp stars are magnetic chemically peculiar early A and late B type stars of the main sequence. They exhibit peculiar surface abundance anomalies that are thought to be the result of gravitational settling and radiative levitation. The physics of diffusion in these stars are reviewed briefly and some model predictions are discussed. While models reproduce some observations reasonably well, more work is needed before the behavior of diffusing elements in a complex magnetic field is fully understood.

  15. Diffusion and Settling in Ap/Bp Stars

    Energy Technology Data Exchange (ETDEWEB)

    Turcotte, S

    2003-04-09

    Ap/Bp stars are magnetic chemically peculiar early A and late B type stars of the main sequence. They exhibit peculiar surface abundance anomalies that are thought to be the result of gravitational settling and radiative levitation. The physics of diffusion in these stars are reviewed briefly and some model predictions are discussed. While models reproduce some observations reasonably well, more work is needed before the behavior of diffusing elements in a complex magnetic field is fully understood.

  16. Damping insert materials for settling chambers of supersonic wind tunnels

    Science.gov (United States)

    Wu, Jie; Radespiel, Rolf

    2017-03-01

    This study describes the application of a novel damping insert material for reducing the flow fluctuations in a tandem nozzle supersonic wind tunnel. This new damping material is composed of multi-layer stainless steel wired meshes. The influences of the multi-layer mesh, such as the quantity of the mesh layer and the installed location in the settling chamber, to the freestream quality have been investigated. A Pitot probe instrumented with a Kulite pressure sensor and a hot-wire probe are employed to monitor the flow fluctuation in the test section of the wind tunnel. Thereafter, a combined modal analysis is applied for the disturbance qualification. Additionally, the transient Mach number in the test section is measured. The disturbance qualification indicates that the multi-layer mesh performs well in providing reduction of vorticity reduction and acoustic fluctuations. Comparable flow quality of the freestream was also obtained using a combination of flexible damping materials. However, the life-span of the new damping materials is much longer. The time transient of the Mach number measured in the test section indicates that the mean flow is rather constant over run time. Furthermore, the time-averaged pressure along the settling chamber is recorded and it shows the distribution of pressure drop by settling chamber inserts.

  17. Clytostoma callistegioides (Bignoniaceae) wax extract with activity on aphid settling.

    Science.gov (United States)

    Castillo, Lucía; Díaz, Martina; González-Coloma, Azucena; González, Andrés; Alonso-Paz, Eduardo; Bassagoda, María Julia; Rossini, Carmen

    2010-12-01

    A bioassay-guided fractionation of leaf extracts from Clytostoma callistegioides (Cham.) Bureau ex Griseb. (Bignoniaceae) led to isolation of a natural mixture of four fatty acids with anti-insect activity against aphids. The compounds were identified by GC-MS as palmitic, stearic, linoleic and linolenic acids and quantified as their methyl esters. The anti-aphid activity of the natural mixture was traced to linolenic and linoleic acids, as shown by the settling inhibition activity of synthetic samples. Interestingly, the saturated acids (palmitic and stearic) tested alone stimulated settling on one of the tested aphids (Myzus persicae), but not on the other tested species (Rhopalosiphum padi). Although ubiquitous, none of these free acids have been previously reported in this Bignoniaceae species. The leaf surface chemistry, which is likely involved in modulating aphid settling behavior, was further investigated for the occurrence of lipophilic substances by histochemical staining. Short, stalked glandular trichomes, previously undescribed for this species, stained with osmium tetroxide and Sudan III, suggesting that the secretion of the defensive acids is related to these surface trichomes. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Diverse Effects on M1 Signaling and Adverse Effect Liability within a Series of M1 Ago-PAMs.

    Science.gov (United States)

    Rook, Jerri M; Abe, Masahito; Cho, Hyekyung P; Nance, Kellie D; Luscombe, Vincent B; Adams, Jeffrey J; Dickerson, Jonathan W; Remke, Daniel H; Garcia-Barrantes, Pedro M; Engers, Darren W; Engers, Julie L; Chang, Sichen; Foster, Jarrett J; Blobaum, Anna L; Niswender, Colleen M; Jones, Carrie K; Conn, P Jeffrey; Lindsley, Craig W

    2017-01-10

    Both historical clinical and recent preclinical data suggest that the M1 muscarinic acetylcholine receptor is an exciting target for the treatment of Alzheimer's disease and the cognitive and negative symptom clusters in schizophrenia; however, early drug discovery efforts targeting the orthosteric binding site have failed to afford selective M1 activation. Efforts then shifted to focus on selective activation of M1 via either allosteric agonists or positive allosteric modulators (PAMs). While M1 PAMs have robust efficacy in rodent models, some chemotypes can induce cholinergic adverse effects (AEs) that could limit their clinical utility. Here, we report studies aimed at understanding the subtle structural and pharmacological nuances that differentiate efficacy from adverse effect liability within an indole-based series of M1 ago-PAMs. Our data demonstrate that closely related M1 PAMs can display striking differences in their in vivo activities, especially their propensities to induce adverse effects. We report the discovery of a novel PAM in this series that is devoid of observable adverse effect liability. Interestingly, the molecular pharmacology profile of this novel PAM is similar to that of a representative M1 PAM that induces severe AEs. For instance, both compounds are potent ago-PAMs that demonstrate significant interaction with the orthosteric site (either bitopic or negative cooperativity). However, there are subtle differences in efficacies of the compounds at potentiating M1 responses, agonist potencies, and abilities to induce receptor internalization. While these differences may contribute to the differential in vivo profiles of these compounds, the in vitro differences are relatively subtle and highlight the complexities of allosteric modulators and the need to focus on in vivo phenotypic screening to identify safe and effective M1 PAMs.

  19. Effect of sediment settling on controlling golden mussel invasion in water transfer project

    Science.gov (United States)

    Xu, Mengzhen; Wang, Zhaoyin; Bogen, Jim; Pan, Baozhu

    2013-04-01

    Inter-basin water transfer projects have been widely used to solve uneven distribution of water resources and water shortage in China. Along with the transferring of water resources, golden mussel (Limnoperna fortunei), the filter-collector macro-invertebrate species originating from southern China has also been inadvertently transferred to new aquatic environment, resulting in quick and uncontrolled spread of the species. The golden mussels are invasive by nature and endowed with a strong byssus for attaching onto their habitat, allowing them to easily invade natural and artificial aquatic systems, which was resulted in high-density golden mussel attachment that causes serious bio-fouling. Invasion and bio-fouling by golden mussels in water transfer systems has drawn attention widely because it has resulted in high resistance to water flow, corrosion of pipe walls and even clogging of tunnels, as well as causing water pollution and ecological imbalance in the regions that receive water infested with golden mussels. Field investigation was conducted along the East River, which is the main drinking water resource for Cantong province and Hongkong, China, to study the natural habitats of golden mussels. Surveys of water transfer tunnels which carry water from the East River to several big cities in Cantong province were done to study golden mussel invasion and attachment in tunnels. It is found that in the natural habitat, golden mussels mainly attach to bedrock and bank stones and solid surfaces facing upstream, while no golden mussels are attached on the surfaces facing downstream and suffering sediment deposition. In the water transfer tunnels, golden mussel attachment densities of 40,000 individuals/m2 mainly occurred on the portion of tunnel walls which face downwards and thus avoid sedimentation. An experiment was designed to study the effect of sediment settling on golden mussel attachment. The results showed that settling of fine sediment particles affects

  20. 16 CFR 1209.4 - Test procedures for determining settled density.

    Science.gov (United States)

    2010-01-01

    ... SAFETY ACT REGULATIONS INTERIM SAFETY STANDARD FOR CELLULOSE INSULATION The Standard § 1209.4 Test procedures for determining settled density. The settled density of lose fill insulation must be determined.... This section describes the procedure for determining the settled density of loose fill insulation. (a...

  1. On the hindered settling of suspensions of mud and mud-sand mixtures

    NARCIS (Netherlands)

    Dankers, P.J.T.

    2006-01-01

    Highly concentrated suspensions are present in many natural environments. When the concentration becomes large enough, particles start to interfere with each other and their settling velocity reduces. This is called hindered settling. As a result of the reduced settling velocity, particles remain in

  2. On the hindered settling of suspensions of mud and mud-sand mixtures

    NARCIS (Netherlands)

    Dankers, P.J.T.

    2006-01-01

    Highly concentrated suspensions are present in many natural environments. When the concentration becomes large enough, particles start to interfere with each other and their settling velocity reduces. This is called hindered settling. As a result of the reduced settling velocity, particles remain in

  3. 49 CFR 40.395 - Can you settle a PIE proceeding?

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Can you settle a PIE proceeding? 40.395 Section 40... DRUG AND ALCOHOL TESTING PROGRAMS Public Interest Exclusions § 40.395 Can you settle a PIE proceeding... concurrence, settle a PIE proceeding....

  4. Broad analgesic activity of a novel, selective M1 agonist.

    Science.gov (United States)

    Wood, Michael W; Martino, Giovanni; Coupal, Martin; Lindberg, Mattias; Schroeder, Patricia; Santhakumar, Vijayaratnam; Valiquette, Manon; Sandin, Johan; Widzowski, Daniel; Laird, Jennifer

    2017-09-01

    Although the muscarinic receptor family has long been a source of potentially compelling targets for small molecule drug discovery, it was difficult to achieve agonist selectivity within the family. A new class of M1 muscarinic agonists has emerged, and these compounds have been characterized as agonists that activate the receptor at an allosteric site. Members of this class of M1 agonists have been shown to be selective across the muscarinic receptors. However, upon introduction of a novel pharmacologic mechanism, it is prudent to ensure that no new off-target activities have arisen, particularly within the context of in vivo experiments. Reported here, is the in vitro and in vivo characterization of a novel M1 agonist tool compound, PPBI, and demonstrations that the primary biological effects of PPBI are mediated through M1. PPBI reverses d-amphetamine locomotor activity, but fails to do so in transgenic mice that do not express M1. PPBI also reverses a natural deficit in a rat cognition model at a level of exposure which also activates cortical circuitry. Most notably, PPBI is analgesic in a variety of rat and mouse models and the analgesic effect of PPBI is reversed by an M1-preferring antagonist and an M1-selective toxin. Finally, the pharmacokinetic/pharmacodynamic measures of PPBI are compared across multiple endpoints which highlights that activity in models of psychosis and pain require higher exposures than that required in the cognition model. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Selectivity of oxomemazine for the M1 muscarinic receptors.

    Science.gov (United States)

    Lee, S W; Woo, C W; Kim, J G

    1994-12-01

    The binding characteristics of pirenzepine and oxomemazine to muscarinic receptor were studied to evaluate the selectivity of oxomemazine for the muscarinic receptor subtypes in rat cerebral microsomes. Equilibrium dissociation constant (KD) of (-)-[3H]quinuclidinyl benzilate([3H]QNB) determined from saturation isotherms was 64 pM. Analysis of the pirenzepine inhibition curve of [3H]QNB binding to cerebral microsome indicated the presence of two receptor subtypes with high (Ki = 16 nM, M1 receptor) and low (Ki = 400 nM, M3 receptor) affinity for pirenzepine. Oxomemazine also identified two receptor subtypes with about 20-fold difference in the affinity for high (Ki = 84 nM, OH receptor) and low (Ki = 1.65 microM, OL receptor) affinity sites. The percentage populations of M1 and M3 receptors to the total receptors were 61:39, and those of OH and OL receptors 39:61, respectively. Both pirenzepine and oxomemazine increased the KD value for [3H]QNB without affecting the binding site concentrations and Hill coefficient for the [3H]QNB binding. Oxomemazine had a 10-fold higher affinity at M1 receptors than at M3 receptors, and pirenzepine a 8-fold higher affinity at OH receptors than at OL receptors. Analysis of the shallow competition binding curves of oxomemazine for M1 receptors and pirenzepine for OL receptors yielded that 69% of M1 receptors were of OH receptors and the remaining 31% of OL receptors, and that 29% of OL receptors were of M1 receptors and 71% of M3 receptors. However, M3 for oxomemazine and OH for pirenzepine were composed of a uniform population. These results suggest that oxomemazine could be classified as a selective drug for M1 receptors and also demonstrate that rat cerebral microsomes contain three different subtypes of M1, M3 and the other site which is different from M1, M2 and M3 receptors.

  6. M1.3--a small scaffold for DNA origami .

    Science.gov (United States)

    Said, Hassan; Schüller, Verena J; Eber, Fabian J; Wege, Christina; Liedl, Tim; Richert, Clemens

    2013-01-07

    The DNA origami method produces programmable nanoscale objects that form when one long scaffold strand hybridizes to numerous oligonucleotide staple strands. One scaffold strand is dominating the field: M13mp18, a bacteriophage-derived vector 7249 nucleotides in length. The full-length M13 is typically folded by using over 200 staple oligonucleotides. Here we report the convenient preparation of a 704 nt fragment dubbed "M1.3" as a linear or cyclic scaffold and the assembly of small origami structures with just 15-24 staple strands. A typical M1.3 origami is large enough to be visualized by TEM, but small enough to show a cooperativity in its assembly and thermal denaturation that is reminiscent of oligonucleotide duplexes. Due to its medium size, M1.3 origami with globally modified staples is affordable. As a proof of principle, two origami structures with globally 5'-capped staples were prepared and were shown to give higher UV-melting points than the corresponding assembly with unmodified DNA. M1.3 has the size of a gene, not a genome, and may function as a model for gene-based nanostructures. Small origami with M1.3 as a scaffold may serve as a workbench for chemical, physical, and biological experiments.

  7. Surface properties of new virginiamycin M(1) derivatives.

    Science.gov (United States)

    Nott, Katherine; Paquot, Michel; Dufour, Samuel; Eeman, Marc; Deleu, Magali

    2009-03-01

    Three kinds of derivatives of the M(1) factor of virginiamycin have been synthesised: esters with long chain fatty acids, oximes with modified polar amino acids and bis-derivatives with both the ester and oxime function. The study of the surface tension time dependence of M(1) and its derivatives has shown that it is necessary to enhance simultaneously the hydrophobicity and the hydrophilicity of M(1) to render M(1) surface-active. A structure/function relationship study of the surface-active bis-derivatives has shown that enhancing the hydrophobicity of the molecule led to slower adsorption kinetics, higher stability of the monolayers formed and a better capacity to penetrate a membrane model. The repulsive electrostatic forces due to the presence of charges on the amino acids linked to M(1) lead to higher surface tensions, a greater molecular area at the interface and lower penetration into a membrane model. This study has demonstrated that modifying systematically the hydrophobicity and hydrophilicity of a non surface-active molecule allows the production of surface-active derivatives.

  8. Genomic characterization of Campylobacter jejuni strain M1.

    Directory of Open Access Journals (Sweden)

    Carsten Friis

    Full Text Available Campylobacter jejuni strain M1 (laboratory designation 99/308 is a rarely documented case of direct transmission of C. jejuni from chicken to a person, resulting in enteritis. We have sequenced the genome of C. jejuni strain M1, and compared this to 12 other C. jejuni sequenced genomes currently publicly available. Compared to these, M1 is closest to strain 81116. Based on the 13 genome sequences, we have identified the C. jejuni pan-genome, as well as the core genome, the auxiliary genes, and genes unique between strains M1 and 81116. The pan-genome contains 2,427 gene families, whilst the core genome comprised 1,295 gene families, or about two-thirds of the gene content of the average of the sequenced C. jejuni genomes. Various comparison and visualization tools were applied to the 13 C. jejuni genome sequences, including a species pan- and core genome plot, a BLAST Matrix and a BLAST Atlas. Trees based on 16S rRNA sequences and on the total gene families in each genome are presented. The findings are discussed in the background of the proven virulence potential of M1.

  9. Investigation of aflatoxin M1 degradation in milk

    Directory of Open Access Journals (Sweden)

    Smajlović Ahmed

    2012-01-01

    Full Text Available Aflatoxin M1 is a highly toxic 4-hydroxylated metabolite of aflatoxins B1 and B2. It is one of the most potent hepatocarcinogens, mutagens, teratogens and immunosuppressors. Feed is often contaminated with aflatoxigenic moulds and aflatoxins with a high possibility of contaminating milk and dairy products with aflatoxin M1. Samples of artificially contaminated milk were exposed to the effects of physical conditions (temperature of -18oC and for microwaves in a microwave oven, time (during the period from 1 to 12 months and a combination of the above mentioned conditions. Following this, levels of aflatoxin M1 degradation were established by using the ELISA method. An insignificant decrease in concentration of toxin was observed which indicates that a temperature of -18°C does not significantly influence the concentration of aflatoxin M1 in the artificially contaminated milk. At the same time, treatment of milk with microwaves in a microwave oven showed an insignificant influence on the percentage of aflatoxin M1 absorbance.

  10. Removal of Heavy Metals and PAH in Retention Basins

    DEFF Research Database (Denmark)

    Larsen, Torben; Neerup-Jensen, Ole

    2004-01-01

    Solid seperation in retention basins is strongly non-linear and depends significantly on the flow rate and the settling characteristics of the particles. Accordingly the calculation of the annual loads of pollutants from storm overflows including basins is rather complex and time consuming....... The paper describes how laboratory investigations and CFD-modelling of flow dependant particle separation in retention basins are combined with long-simulation of storm water overflows including basins based on historical time series of rainfalls also taking into account the flow dependant solid seperation...... in order to calculate annual loads of pollutants from urban catchments. The study cover Cd, Cu, Ni, Pb, Zn and PAH....

  11. Settling for less out of fear of being single.

    Science.gov (United States)

    Spielmann, Stephanie S; MacDonald, Geoff; Maxwell, Jessica A; Joel, Samantha; Peragine, Diana; Muise, Amy; Impett, Emily A

    2013-12-01

    The present research demonstrates that fear of being single predicts settling for less in romantic relationships, even accounting for constructs typically examined in relationship research such as anxious attachment. Study 1 explored the content of people's thoughts about being single. Studies 2A and 2B involved the development and validation of the Fear of Being Single Scale. Study 2C provided preliminary support for the hypothesis that fear of being single predicts settling for less in ongoing relationships, as evidenced by greater dependence in unsatisfying relationships. Study 3 replicated this effect in a longitudinal study demonstrating that fear of being single predicts lower likelihood of initiating the dissolution of a less satisfying relationship. Studies 4A and 4B explored the predictive ability of fear of being single for self-reported dating standards. Across both samples, fear of being single was unrelated to self-reported standards for a mate, with the exception of consistently higher standards for parenting. Studies 5 and 6 explored romantic interest in targets that were manipulated to vary in responsiveness and physical attractiveness. These studies found that fear of being single consistently predicted romantic interest in less responsive and less attractive dating targets. Study 7 explored fear of being single during a speed-dating event. We found that fear of being single predicted being less selective in expressing romantic interest but did not predict other daters' romantic interest. Taken together, the present research suggests that fear of being single is a meaningful predictor of settling for less in relationships.

  12. Modelling and test of aeration tank settling (ATS)

    DEFF Research Database (Denmark)

    Nielsen, M. K.; Bechmann, H.; Henze, Mogens

    2000-01-01

    that a qualitatively correct model can be established. The simplicity of the model allows for on-line identification of the necessary parameters, so that no maintenance is needed to use of the on-line model for control. The practical implementation on three plants indicates that implementation of STAR with ATS control......The use of aeration tank settling during high hydraulic loads on large wastewater treatment plants has previously been demonstrated as a reliable technique and proven valuable. The paper proposes a simplified deterministic model to predict the efficiency of the method. It is shown...

  13. Continuity waves in fully resolved simulations of settling particles

    Science.gov (United States)

    Willen, Daniel; Sierakowski, Adam; Prosperetti, Andrea

    2016-11-01

    Fully resolved simulations of 500 to 2,000 particles settling in a fluid have been conducted with the Physalis method. A new approach to the reconstruction of pseudo-continuum fields is described and is used to examine the results with the purpose of identifying concentration waves. The velocity of concentration waves is successfully deduced from the simulations. A comparison of the results with continuity wave theory shows good agreement. Several new insights about the particle microstructure conditionally averaged on volume fraction and velocity are also described. This work is supported by NSF award CBET1335965.

  14. New Anabaena and Nostoc cyanophages from sewage settling ponds

    Energy Technology Data Exchange (ETDEWEB)

    Hu, N.; Thiel, T.; Giddings, T.H., Jr.; Wolk, C.P.

    1981-10-15

    We have isolated, from sewage settling ponds, 16 cyanophages for heterocyst forming, filamentous cyanobacteria of the genera Anabaena and Nostoc. These phages fall into three groups based on morphology, host range, one-step growth curves, and restriction digests. On the basis of these criteria they can be distinguished from cyanophages A-1(L), A-4(L), N-1, and AN-10 which we received from other laboratories. Certain of the newly described phages are similar in morphology to the short-tailed LPP cyanophages, and others to the long-tailed AS cyanophages.

  15. A simple formula for predicting settling velocity of sediment particles

    Directory of Open Access Journals (Sweden)

    Song Zhiyao

    2008-03-01

    Full Text Available Based on the general relationship described by Cheng between the drag coefficient and the Reynolds number of a particle, a new relationship between the Reynolds number and a dimensionless particle parameter is proposed. Using a trial-and-error procedure to minimize errors, the coefficients were determined and a formula was developed for predicting the settling velocity of natural sediment particles. This formula has higher prediction accuracy than other published formulas and it is applicable to all Reynolds numbers less than 2×105.

  16. Settling of virgin olive oil from horizontal screw solid bowl in static conditions.

    Science.gov (United States)

    Gila, Abraham M; Bejaoui, Mohamed A; Beltrán, Gabriel; Jiménez, Antonio

    2017-08-01

    This work was aimed to study the clarification efficiency of natural decantation in settling tank on virgin olive oil obtained from a two-ways continuous process. For this purpose, the impurities content of the virgin olive oil were monitored during settling process in settling tank at two different depths. Efficiency of purging system was determined for two days. The experiments were performed at industrial scale during three crop years. During the first minutes of settling was observed an ascent of the smaller organic particles of the oil. Then, most of the virgin olive oil impurities were settled at 300 min, independently of the initial content of virgin olive oil. Finally, oil decantation showed slower rate. Higher clarification values were obtained for those decanter oils with higher impurities content, achieving clarification percentages between of 62.69 and 95.91% at 48 h of settling. The highest settling efficiency was observed for those decanter oils with initial higher impurities content. The purging system used in the settling tanks was not able to remove the most of settled impurities since a considerable amount of the impurities remained in the tank after 48 h, between 13.6 and 71.41% for the studied oils. In the tank purges was observed important oil losses. Therefore, decantation was not an efficient system for oil clarification since its settling capacity varied depending on the initial impurities content and due to the settled impurities can not be removed fully by purging system.

  17. Concerning the Integral dx/x[superscript m] (1+x)

    Science.gov (United States)

    Walters, William; Huber, Michael

    2010-01-01

    Consider the integral dx/x[superscript m] (1+x). In the "CRC Standard Mathematical Tables," this integral can require repeated integral evaluations. Enter this integral into your favourite computer algebra system, and the results may be unrecognizable. In this article, we seek to provide a simpler evaluation for integrals of this form. We state up…

  18. Theory of the M = 1 Kink Mode in Toroidal Plasma

    NARCIS (Netherlands)

    de Blank, H. J.; Schep, T. J.

    1991-01-01

    The energy principle of ideal magnetohydrodynamics (MHD) is used to study the ideal MHD stability of the m = 1 internal kink mode in a toroidal plasma. The equilibrium configurations that are considered allow for a broad region where the safety factor q is close to unity. This region may extend to t

  19. Concerning the Integral dx/x[superscript m] (1+x)

    Science.gov (United States)

    Walters, William; Huber, Michael

    2010-01-01

    Consider the integral dx/x[superscript m] (1+x). In the "CRC Standard Mathematical Tables," this integral can require repeated integral evaluations. Enter this integral into your favourite computer algebra system, and the results may be unrecognizable. In this article, we seek to provide a simpler evaluation for integrals of this form. We state up…

  20. Removal of Heavy Metals and PAH in Retention Basins

    DEFF Research Database (Denmark)

    Larsen, Torben; Neerup-Jensen, Ole

    2004-01-01

    Solid seperation in retention basins is strongly non-linear and depends significantly on the flow rate and the settling characteristics of the particles. Accordingly the calculation of the annual loads of pollutants from storm overflows including basins is rather complex and time consuming. The p...... in order to calculate annual loads of pollutants from urban catchments. The study cover Cd, Cu, Ni, Pb, Zn and PAH....

  1. Analysis of suspended solids transport processes in primary settling tanks.

    Science.gov (United States)

    Patziger, Miklós; Kiss, Katalin

    2015-01-01

    The paper shows the results of a long-term research comprising FLUENT-based numerical modeling, in situ measurements and laboratory tests to analyze suspended solids (SS) transport processes in primary settling tanks (PSTs). The investigated PST was one of the rectangular horizontal flow PSTs at a large municipal wastewater treatment plant (WWTP) of a capacity of 500,000 population equivalent. Many middle-sized and large WWTPs are equipped with such PSTs. The numerical PST model was calibrated and validated based on the results of comprehensive in situ flow and SS concentration measurements from low (5 m/h) up to quite high surface overflow rates of 9.5 and 13.0 m/h and on settling and other laboratory tests. The calibrated and validated PST model was also successfully used for evaluation of some slight modifications of the inlet geometry (removing lamellas, installing a flocculation 'box', shifting the inlet into a 'bottom-near' or into a 'high' position), which largely affect PST behavior and performance. The investigations provided detailed insight into the flow and SS transport processes within the investigated PST, which strongly contributes to hydrodynamically driven design and upgrading of PSTs.

  2. Dust Transport in Protostellar Disks Through Turbulence and Settling

    CERN Document Server

    Turner, N J; Sano, T

    2009-01-01

    We apply ionization balance and MHD calculations to investigate whether magnetic activity moderated by recombination on dust can account for the mass accretion rates and the mid-infrared spectra and variability of protostellar disks. The MHD calculations use the stratified shearing-box approach and include grain settling and the feedback from the changing dust abundance on the resistivity of the gas. The two-decade spread in accretion rates among T Tauri stars is too large to result solely from variety in the grain size and stellar X-ray luminosity, but can be produced by varying these together with the disk magnetic flux. The diversity in the silicate bands can come from the coupling of grain settling to the distribution of the magneto-rotational turbulence, through three effects: (1) Recombination on grains yields a magnetically inactive dead zone extending above two scale heights, while turbulence in the magnetically active disk atmosphere overshoots the dead zone boundary by only about one scale height. (...

  3. Finite elements model of a rotating half-bridge belonging to a circular settling tank

    Science.gov (United States)

    Dascalescu, A. E.; Lazaroiu, G.; Scupi, A. A.; Oanta, E.

    2016-08-01

    A circular settling tank is an open reservoir used for the gravitational separation of the sludge and of the clarified water which is discharged in the launder which is mounted at the periphery of the basin. The extraction of the sludge is done by the use of a rotating half-bridge which sweeps the sludge, vacuums it using a system of scrapping blades and suction pipes, collects it in some local sludge chambers and pour it in a central collecting tank. The rotating half-bridge is a complex structure under a complex system of loads, therefore advanced instruments of investigation are required to assess the state of strains and stresses in this structure. Until now an analytical model was developed based on the hypotheses specific to the strength of materials academic discipline. The numerical models presented in the paper use the finite element method to determine the displacements of the main beam loaded by the weight of the structure and by the Archimedes’ forces. The results of the models developed so far are conclusive for the future directions of research which aims a higher degree of accuracy of the models and of the according research methodology.

  4. Quantitative detection of settled coal dust over green canopy

    Science.gov (United States)

    Brook, Anna; Sahar, Nir

    2017-04-01

    The main task of environmental and geoscience applications are efficient and accurate quantitative classification of earth surfaces and spatial phenomena. In the past decade, there has been a significant interest in employing spectral unmixing in order to retrieve accurate quantitative information latent in in situ data. Recently, the ground-truth and laboratory measured spectral signatures promoted by advanced algorithms are proposed as a new path toward solving the unmixing problem in semi-supervised fashion. This study presents a practical implementation of field spectroscopy as a quantitative tool to detect settled coal dust over green canopy in free/open environment. Coal dust is a fine powdered form of coal, which is created by the crushing, grinding, and pulverizing of coal. Since the inelastic nature of coal, coal dust can be created during transportation, or by mechanically handling coal. Coal dust, categorized at silt-clay particle size, of particular concern due to heavy metals (lead, mercury, nickel, tin, cadmium, mercury, antimony, arsenic, isotopes of thorium and strontium) which are toxic also at low concentrations. This hazard exposes risk on both environment and public health. It has been identified by medical scientist around the world as causing a range of diseases and health problems, mainly heart and respiratory diseases like asthma and lung cancer. It is due to the fact that the fine invisible coal dust particles (less than 2.5 microns) long lodge in the lungs and are not naturally expelled, so long-term exposure increases the risk of health problems. Numerus studies reported that data to conduct study of geographic distribution of the very fine coal dust (smaller than PM 2.5) and related health impacts from coal exports, is not being collected. Sediment dust load in an indoor environment can be spectrally assessed using reflectance spectroscopy (Chudnovsky and Ben-Dor, 2009). Small amounts of particulate pollution that may carry a signature

  5. The E2/M1 ratio in {Delta} photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Hoblit, S. [Brookhaven National Lab., Upton, NY (United States). Physics Dept.]|[Univ. of Virginia, Charlottesville, VA (United States). Dept. of Physics; Blanpied, G. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Physics; Blecher, M. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Physics Dept.] [and others; LEGS Collaboration

    1997-10-01

    New high-precision measurements of p({rvec {gamma}}, {pi}) and p({rvec {gamma}}, {gamma}) cross sections and beam asymmetries have been combined with other polarization ratios in a simultaneous analysis of both reactions. The E2/M1 mixing ratio for the n {r_arrow} {Delta} transition extracted from this analysis is EMR = {minus}3.0% {+-} 0.3 (stat+sys) {+-} 0.2 (model).

  6. Insights on tephra settling velocity from morphological observations

    Science.gov (United States)

    Alfano, Fabrizio; Bonadonna, Costanza; Delmelle, Pierre; Costantini, Licia

    2011-12-01

    In this study we present a systematic and detailed morphological characterization of tephra particles from different eruptions (Fontana Lapilli, Masaya, Nicaragua; Keanakāko'i Formation, Kilauea, USA; recent dome explosions of Soufriere Hills volcano, Montserrat) and the calculation of their Terminal Fall Velocity (TFV) as obtained based on different drag prediction models (i.e., Wilson and Huang, 1979; Haider and Levenspiel, 1989; Ganser, 1993; Dellino et al., 2005). In particular, particle sphericity, and, therefore, particle surface area, is essential for the calculation of TFV of irregular-shape particles but is of complex determination. Various attempts have been proposed. According to our results, 2D morphological characterization of volcanic particles is a fast and simple application for a wide range of particle size and provides consistent sphericity and settling-velocity values. 3D scanning also provides a promising tool for lapilli-sized tephra (> 2 cm). In contrast, gas-adsorption-derived surface area is not suitable for the calculation of TFV of volcanic particles mostly because it mainly describes the surface contribution of nanometric pores that are not expected to affect significantly TFV and because bulk-sample analysis is representative of neither individual particles nor of the whole particle population. Settling velocities calculated using values of surface area derived from gas adsorption analyses are up to two orders of magnitude lower than the values obtained through 2D analysis. In addition, our results also show how the influence of particle shape on TFV increases with particle size. In particular, calculated TFV converges at small particle sizes (≥ 3 ϕ) regardless of the model applied, suggesting that the spherical assumption is appropriate for this size fraction (discrepancies with the spherical model are within 10%). Discrepancies with the spherical model increase with particle size up to about 50% and depend on the choice of both the

  7. The E2/M1 ratio in {Delta} photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Sandorfi, A.M. [Brookhaven National Lab., Upton, NY (United States). Physics Dept.; Blanpied, G. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Physics; Blecher, M. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Physics Dept.] [and others; LEGS Collaboration

    1997-08-01

    The properties of the transition from the nucleon to the {Delta}(1232) serve as a benchmark for models of nucleon structure. To first order, N {r_arrow} {Delta} photo-excitation is dominated by a simple M1 quark spin-flip transition. At higher order, small L = 2 components in the N and {Delta} wavefunctions allow this excitation to proceed via an electric quadrupole transition. Since Nucleon models differ greatly on the mechanisms used to generate these L = 2 components,, the ratio of E2/M1 transitions (EMR) provides a sensitive test for structure models. Here, new high-precision measurements of p({rvec {gamma}}, {pi}) and p({rvec {gamma}}, {gamma}) cross sections and beam asymmetries have been combined with other polarization ratios in a simultaneous analysis of both reactions. Compton scattering has provided two important new constraints on the photo-pion amplitude. The E2/M1 mixing ratio for the N {r_arrow} {Delta} transition extracted from this analysis is EMR = {minus}3.0% {+-} 0.3 (stat+sys) {+-} 0.2 (model).

  8. Estimate of Hanford Waste Rheology and Settling Behavior

    Energy Technology Data Exchange (ETDEWEB)

    Poloski, Adam P.; Wells, Beric E.; Tingey, Joel M.; Mahoney, Lenna A.; Hall, Mark N.; Thomson, Scott L.; Smith, Gary Lynn; Johnson, Michael E.; Meacham, Joseph E.; Knight, Mark A.; Thien, Michael G.; Davis, Jim J.; Onishi, Yasuo

    2007-10-26

    The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment and Immobilization Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site. Piping, pumps, and mixing vessels have been selected to transport, store, and mix the high-level waste slurries in the WTP. This report addresses the analyses performed by the Rheology Working Group (RWG) and Risk Assessment Working Group composed of Pacific Northwest National Laboratory (PNNL), Bechtel National Inc. (BNI), CH2M HILL, DOE Office of River Protection (ORP) and Yasuo Onishi Consulting, LLC staff on data obtained from documented Hanford waste analyses to determine a best-estimate of the rheology of the Hanford tank wastes and their settling behavior. The actual testing activities were performed and reported separately in referenced documentation. Because of this, many of the required topics below do not apply and are so noted.

  9. Experiments in reduced gravity sediment settling on Mars

    CERN Document Server

    Kuhn, Nikolaus

    2014-01-01

    Experiments in Reduced Gravity: Sediment Settling on Mars is the first book to be published that reflects experiments conducted on Martian geomorphology in reduced gravity. This brief yet important book on sediment experiments assesses the theoretical and empirical foundation of the models used to analyze the increasing information we have on the past geography on Mars. The book also evaluates the need to develop new methods for analyzing new information by providing a conceptual outline and a case study on how experiments can be used to test current theoretical considerations. The conceptual approach to identifying the need for and role of experiments will be of interest to planetary scientists and geoscientists not necessarily involved with Mars, but those using experiments in their research who can apply the book's concepts. Includes figures, diagrams, illustrations, and photographs to vividly explore experiments and outcomes in reduced gravity Provides an outline of planned experiments and questions relat...

  10. Settling-velocity specific SOC distribution on hillslopes

    DEFF Research Database (Denmark)

    Hu, Yaxian; Berhe, Asmeret Asefaw; Fogel, Marilyn L.;

    The net effect of soil erosion by water, as a sink or source of atmospheric CO2, is determined by the spatial (re-)distribution and stability of eroded soil organic carbon (SOC). The depositional position of eroded SOC is a function of the transport distances of soil fractions where the SOC...... is stored. In theory, the transport distances of soil fractions are related to their settling velocities under given flow conditions. Yet, very few field investigations have been conducted to examine the actual movement of eroded soil fractions along hillslopes, let alone the re-distribution pattern of SOC...... shows a coarsening effect immediately below the eroding slope, followed by a fining trend at the slope tail. The 13C values of soil fractions were more positive at the footslope than on the slope shoulder or at the slope tail, suggesting enhanced decomposition rate of fresh SOC input at the footslope...

  11. Settling the Complexity of Computing Two-Player Nash Equilibria

    CERN Document Server

    Chen, Xi; Teng, Shang-Hua

    2007-01-01

    We settle a long-standing open question in algorithmic game theory. We prove that Bimatrix, the problem of finding a Nash equilibrium in a two-player game, is complete for the complexity class PPAD Polynomial Parity Argument, Directed version) introduced by Papadimitriou in 1991. This is the first of a series of results concerning the complexity of Nash equilibria. In particular, we prove the following theorems: Bimatrix does not have a fully polynomial-time approximation scheme unless every problem in PPAD is solvable in polynomial time. The smoothed complexity of the classic Lemke-Howson algorithm and, in fact, of any algorithm for Bimatrix is not polynomial unless every problem in PPAD is solvable in randomized polynomial time. Our results demonstrate that, even in the simplest form of non-cooperative games, equilibrium computation and approximation are polynomial-time equivalent to fixed point computation. Our results also have two broad complexity implications in mathematical economics and operations res...

  12. System Description for the KW Basin Integrated Water Treatment System (IWTS) (70.3)

    Energy Technology Data Exchange (ETDEWEB)

    DERUSSEAU, R.R.

    2000-04-18

    This is a description of the system that collects and processes the sludge and radioactive ions released by the spent nuclear fuel (SNF) processing operations conducted in the 105 KW Basin. The system screens, settles, filters, and conditions the basin water for reuse. Sludge and most radioactive ions are removed before the water is distributed back to the basin pool. This system is part of the Spent Nuclear Fuel Project (SNFP).

  13. The impact of the adult blue mussel (Mytilus edulis) population on settling of conspecific larvae

    DEFF Research Database (Denmark)

    Dolmer, Per; Stenalt, Ea

    2010-01-01

    -settling mortality may be due to a reduced benthic predation in habitats with high complexity. In a field experiment, the larval settling of blue mussels, Mytilus edulis, was recorded on an artificial substrate 0.25, 1 and 2 m above the bottom during six periods in spring 1999. The experiment was conducted at four....... A size analysis of the settled mussels indicated that the reduction in settling intensity close to mussel beds was due to a pre-settling process: the larvae were predated by the filtering adult mussels. Settling was significantly affected by wind stress. During periods with a high mean wind velocity...... and a turbulent water column, the larvae showed a reduced settlement 1 m above a mussel bed relative to 2 m above, whereas the same patterns not could be observed outside a mussel bed. The importance of the filtration activity of the adult mussels and the behaviour of the larvae is discussed. The recruitment...

  14. Development of a new model for batch sedimentation and application to secondary settling tanks design.

    Science.gov (United States)

    Karamisheva, Ralica D; Islam, M A

    2005-01-01

    Assuming that settling takes place in two zones (a constant rate zone and a variable rate zone), a model using four parameters accounting for the nature of the water-suspension system has been proposed for describing batch sedimentation processes. The sludge volume index (SVI) has been expressed in terms of these parameters. Some disadvantages of the SVI application as a design parameter have been pointed out, and it has been shown that a relationship between zone settling velocity and sludge concentration is more consistent for describing the settling behavior and for design of settling tanks. The permissible overflow rate has been related to the technological parameters of secondary settling tank by simple working equations. The graphical representations of these equations could be used to optimize the design and operation of secondary settling tanks.

  15. Effect of the radial plasma nonuniformity on the propagation of guided m = + 1 and m = - 1 modes in helicon discharges

    Science.gov (United States)

    Aliev, Yu. M.; Krämer, M.

    2016-10-01

    Theoretical as well as numerical analyses of the full set of Maxwell's equations is carried out to study non-axisymmetric ( m ≠ 0 ) guided modes in radially nonuniform helicon (HE) discharges. Unlike the axisymmetric (m = 0) modes, these modes reveal a non-reciprocal behavior with respect to the azimuthal direction. We develop the conditions for propagation and non-propagation of the various modes in the helicon parameter range, thereby focussing on the important role of the radial density gradient. Three types of modes occurring in different parameter ranges are described, i.e., the helicon (HE) mode, the electrostatic (ES) or Trivelpiece-Gould mode, and the locally coupled (LC) mode that is characterized by mode coupling (MC) in a certain region of the plasma density profile. In contrast to m = + 1 modes, the parameter range of m = - 1 modes is much more restricted as rather high densities are needed for the propagation of the helicon and LC modes. An important issue of the investigations is the rf power coupling and absorption via the various modes. Computations based on a simple antenna-plasma model show that the axial wavenumber of the antenna determines decisively which type of mode is excited. In case of LC mode excitation, the dominant role of the MC layer for the absorption is demonstrated. Finally, the rf power coupling to helicon modes is studied. The density limit for m = - 1 helicon mode propagation and the narrow magnetic field profiles of these modes are the main reasons why the rf power absorption in helicon discharges occurs via m = + 1 helicon modes.

  16. Electrochemical immunochip sensor for aflatoxin M1 detection.

    Science.gov (United States)

    Parker, Charlie O; Lanyon, Yvonne H; Manning, Mary; Arrigan, Damien W M; Tothill, Ibtisam E

    2009-07-01

    An investigation into the fabrication, electrochemical characterization, and development of a microelectrode array (MEA) immunosensor for aflatoxin M(1) is presented in this paper. Gold MEAs (consisting of 35 microsquare electrodes with 20 microm x 20 microm dimensions and edge-to-edge spacing of 200 microm) together with on-chip reference and counter electrodes were fabricated using standard photolithographic methods. The MEAs were then characterized by cyclic voltammetry, and the behavior of the on-chip electrodes were evaluated. The microarray sensors were assessed for their applicability to the development of an immunosensor for the analysis of aflatoxin M(1) directly in milk samples. Following the sensor surface silanization, antibodies were immobilized by cross-linking with 1,4-phenylene diisothiocyanate (PDITC). Surface characterization was conducted by electrochemistry, fluorescence microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). A competitive enzyme linked immunosorbent assay (ELISA) assay format was developed on the microarray electrode surface using the 3,3,5',5'-tetramethylbenzidine dihyrochloride (TMB)/H(2)O(2) electrochemical detection scheme with horseradish peroxidase (HRP) as the enzyme label. The performance of the assay and the microarray sensor were characterized in pure buffer conditions before applying to the milk samples. With the use of this approach, the detection limit for aflatoxin M(1) in milk was estimated to be 8 ng L(-1), with a dynamic detection range of 10-100 ng L(-1), which meets present legislative limits of 50 ng L(-1). The milk interference with the sensor surface was also found to be minimal. These devices show high potential for development of a range of new applications which have previously only been detected using elaborate instrumentation.

  17. A review of aflatoxin M1 in liquid milk

    OpenAIRE

    2015-01-01

    Mycotoxins continue to pose a health concern via human exposure to contaminated food. Aflatoxin M1 (AFM1), the hydroxylated metabolite of aflatoxin B1 (AFB1), may be found in the milk of dairy cattle and other mammals. In humans, AFM1 is excreted through the feces, urine, and in the case of lactating mothers, also in breast milk after consumption of aflatoxin contaminated food. Concentration of AFM1 in milk is a function of several factors, namely: animal type, milking day, milk yield, season...

  18. PEMBUATAN PROGRAM INTERFACE UNTUK PENGONTROLAN RV-M1

    Directory of Open Access Journals (Sweden)

    Endra Endra

    2007-10-01

    Full Text Available Article explores the making of interface of RV-M1 hand robot control that replaced the cosiprog program,a program that is able to help student in Mecatronica-1 Practice, and able to control the hand robot by localnetwork by two user or more. The used methods were literature study, and field study, that is design method. Theresearch result are control of hand robot on X,Y,Z axis and point to point, the use of local network to control thehand robot, save certain position, and use several user to control the robot.Keywords: interface program, robot, local network

  19. E1 and M1 strength functions at low energy

    Directory of Open Access Journals (Sweden)

    Schwengner Ronald

    2017-01-01

    Full Text Available We report photon-scattering experiments using bremsstrahlung at the γELBE facility of Helmholtz-Zentrum Dresden-Rossendorf and using quasi-monoenergetic, polarized γ beams at the HIγS facility of the Triangle Universities Nuclear Laboratory in Durham. To deduce the photoabsorption cross sections at high excitation energy and high level density, unresolved strength in the quasicontinuum of nuclear states has been taken into account. In the analysis of the spectra measured by using bremsstrahlung at γELBE, we perform simulations of statistical γ-ray cascades using the code γDEX to estimate intensities of inelastic transitions to low-lying excited states. Simulated average branching ratios are compared with model-independent branching ratios obtained from spectra measured by using monoenergetic γ beams at HIγS. E1 strength in the energy region of the pygmy dipole resonance is discussed in nuclei around mass 90 and in xenon isotopes. M1 strength in the region of the spin-flip resonance is also considered for xenon isotopes. The dipole strength function of 74Ge deduced from γELBE experiments is compared with the one obtained from experiments at the Oslo Cyclotron Laboratory. The low-energy upbend seen in the Oslo data is interpreted as M1 strength on the basis of shell-model calculations.

  20. Quantitative detection of settled dust over green canopy

    Science.gov (United States)

    Brook, Anna

    2016-04-01

    The main task of environmental and geoscience applications are efficient and accurate quantitative classification of earth surfaces and spatial phenomena. In the past decade, there has been a significant interest in employing hyperspectral unmixing in order to retrieve accurate quantitative information latent in hyperspectral imagery data. Recently, the ground-truth and laboratory measured spectral signatures promoted by advanced algorithms are proposed as a new path toward solving the unmixing problem of hyperspectral imagery in semi-supervised fashion. This paper suggests that the sensitivity of sparse unmixing techniques provides an ideal approach to extract and identify dust settled over/upon green vegetation canopy using hyperspectral airborne data. Atmospheric dust transports a variety of chemicals, some of which pose a risk to the ecosystem and human health (Kaskaoutis, et al., 2008). Many studies deal with the impact of dust on particulate matter (PM) and atmospheric pollution. Considering the potential impact of industrial pollutants, one of the most important considerations is the fact that suspended PM can have both a physical and a chemical impact on plants, soils, and water bodies. Not only can the particles covering surfaces cause physical distortion, but particles of diverse origin and different chemistries can also serve as chemical stressors and cause irreversible damage. Sediment dust load in an indoor environment can be spectrally assessed using reflectance spectroscopy (Chudnovsky and Ben-Dor, 2009). Small amounts of particulate pollution that may carry a signature of a forthcoming environmental hazard are of key interest when considering the effects of pollution. According to the most basic distribution dynamics, dust consists of suspended particulate matter in a fine state of subdivision that are raised and carried by wind. In this context, it is increasingly important to first, understand the distribution dynamics of pollutants, and

  1. Estimating the settling velocity of bioclastic sediment using common grain-size analysis techniques

    Science.gov (United States)

    Cuttler, Michael V. W.; Lowe, Ryan J.; Falter, James L.; Buscombe, Daniel D.

    2017-01-01

    Most techniques for estimating settling velocities of natural particles have been developed for siliciclastic sediments. Therefore, to understand how these techniques apply to bioclastic environments, measured settling velocities of bioclastic sedimentary deposits sampled from a nearshore fringing reef in Western Australia were compared with settling velocities calculated using results from several common grain-size analysis techniques (sieve, laser diffraction and image analysis) and established models. The effects of sediment density and shape were also examined using a range of density values and three different models of settling velocity. Sediment density was found to have a significant effect on calculated settling velocity, causing a range in normalized root-mean-square error of up to 28%, depending upon settling velocity model and grain-size method. Accounting for particle shape reduced errors in predicted settling velocity by 3% to 6% and removed any velocity-dependent bias, which is particularly important for the fastest settling fractions. When shape was accounted for and measured density was used, normalized root-mean-square errors were 4%, 10% and 18% for laser diffraction, sieve and image analysis, respectively. The results of this study show that established models of settling velocity that account for particle shape can be used to estimate settling velocity of irregularly shaped, sand-sized bioclastic sediments from sieve, laser diffraction, or image analysis-derived measures of grain size with a limited amount of error. Collectively, these findings will allow for grain-size data measured with different methods to be accurately converted to settling velocity for comparison. This will facilitate greater understanding of the hydraulic properties of bioclastic sediment which can help to increase our general knowledge of sediment dynamics in these environments.

  2. Microthrix parvicella abundance associates with activated sludge settling velocity and rheology - Quantifying and modelling filamentous bulking.

    Science.gov (United States)

    Wágner, Dorottya S; Ramin, Elham; Szabo, Peter; Dechesne, Arnaud; Plósz, Benedek Gy

    2015-07-01

    The objective of this work is to identify relevant settling velocity and rheology model parameters and to assess the underlying filamentous microbial community characteristics that can influence the solids mixing and transport in secondary settling tanks. Parameter values for hindered, transient and compression settling velocity functions were estimated by carrying out biweekly batch settling tests using a novel column setup through a four-month long measurement campaign. To estimate viscosity model parameters, rheological experiments were carried out on the same sludge sample using a rotational viscometer. Quantitative fluorescence in-situ hybridisation (qFISH) analysis, targeting Microthrix parvicella and phylum Chloroflexi, was used. This study finds that M. parvicella - predominantly residing inside the microbial flocs in our samples - can significantly influence secondary settling through altering the hindered settling velocity and yield stress parameter. Strikingly, this is not the case for Chloroflexi, occurring in more than double the abundance of M. parvicella, and forming filaments primarily protruding from the flocs. The transient and compression settling parameters show a comparably high variability, and no significant association with filamentous abundance. A two-dimensional, axi-symmetrical computational fluid dynamics (CFD) model was used to assess calibration scenarios to model filamentous bulking. Our results suggest that model predictions can significantly benefit from explicitly accounting for filamentous bulking by calibrating the hindered settling velocity function. Furthermore, accounting for the transient and compression settling velocity in the computational domain is crucial to improve model accuracy when modelling filamentous bulking. However, the case-specific calibration of transient and compression settling parameters as well as yield stress is not necessary, and an average parameter set - obtained under bulking and good settling

  3. Presence of moulds and aflatoxin M1 in milk

    Directory of Open Access Journals (Sweden)

    Janković Vesna V.

    2009-01-01

    Full Text Available Aflatoxin M1 (AFM1 appears in milk or dairy products as a direct result of the cattle's ingestion of feed contaminated with aflatoxin B1 (AFB1. This study comprises mycological and mycotoxicological investigations of 23 milk samples (raw, infant food, pasteurized, whey and yoghurt. The mycological testing showed dominant presence of genus Geotrichum. G. candidum was found in 9 samples, with the highest contamination in the raw milk samples. The contamination level of AM1 is defined by using direct competitive enzyme- -linked immunosorbent assay (ELISA. AFM1 was found in 9 samples. AFM1 levels were lower than the recommended limits. However, as AFM1 is considered a probable human carcinogen (2B type, it is necessary to achieve a low level of AFM1 in milk. Therefore, cows' feed samples from various cowsheds are supposed to be evaluated routinely for aflatoxin, and kept away from fungal contamination as much as possible.

  4. Aflatoxin M1 Contamination in Ice-Cream

    Directory of Open Access Journals (Sweden)

    R. Kazemi Darsanaki

    2013-06-01

    Full Text Available Aflatoxin M1 (AFM1 is the hydroxylated metabolite of aflatoxin B1 (AFB1 that it can be found in milk and dairy products. In this study, ELISA (Enzyme Linked Immunosorbent Assay technique was used for detection of AFM1 in ice-cream in Guilan province (Northern Iran. A total of 90 ice-cream samples was randomly obtained from different supermarkets. In 62 of the 90 ice-cream samples examined (68.88%, the presence of AFM1 was detected in concentrations between 8.4 -147.7 ng/l. The mean level of AFM1 in positive samples was 40.36 ng/l. AFM1 levels in 11 samples (12.22% were higher than the maximum tolerance limit (50 ng/l accepted by ISIRI, European Community and Codex Alimentarius.

  5. [The BION-M1 project: overview and first results].

    Science.gov (United States)

    Sychev, V N; Ilyin, E A; Yarmanova, E N; Rakov, D V; Ushakov, I B; Kirilin, A N; Orlov, O I; Grigoriev, A I

    2014-01-01

    Biosatellite BION-M1 was launched on April 19 and landed on May 19, 2013. The mission program was largely a continuation of the earlier flown 11 BION projects, FOTON-M2 and FOTON-M3. The biosatellite was inhabited by a great variety of living organisms used for experiments and studies in gravitational physiology, gravitational biology, biotechnology, astrobiology and radiation biology, dosimetry and spectrometry. This was the first time in the history of national biology and physiology when male mice C57bl/6 were chosen for a long-term space experiment focused upon molecular biology investigations. Unfortunately, because of technical failures during the flight a part of the animals were lost. However, the major objectives were attained through reconsideration of biomaterial division among investigators and completion of virtually the total scope of investigations.

  6. Estimating phosphorus concentrations following alum treatment using apparent settling velocity

    Science.gov (United States)

    Panuska, John; Robertson, Dale M.

    2009-01-01

    he apparent settling velocity (Vs) is a term used in empirical, steady-state, mass-balance lake models to represent the net phosphorus flux from the water column. The Vollenweider (1969) mixed-reactor lake model was rearranged and used to calculate Vs values for total phosphorus (TP) for three lakes treated with alum to reduce the internal flux of P to the water column (Delavan Lake, Wisconsin; Lake Morey, Vermont; and West Twin Lake, Ohio). An analysis of Vs values was conducted using data from these three lakes for both the pre- and post-alum treated conditions. Analysis of Vs values for both the pre- and post-alum conditions in Lake Morey and West Twin Lake resulted in a post-treatment mean Vs value of 7 ± 2.0 m·yr−1. The effect of the alum treatment, although short-lived in Delavan Lake, resulted in a mean post-treatment Vs value of 3.4 ± 0.3 m·yr−1. The consistency in the post-treatment Vs values in Lake Morey and West Twin Lake is used to demonstrate a predictive analysis method for water column TP concentrations in lakes following a successful treatment of the anoxic sediment area with alum. Additional pre- and post-alum in-lake and watershed loading data are needed to advance this concept into a management model.

  7. Bilateral patching in retinal detachment: fluid mechanics and retinal "settling".

    Science.gov (United States)

    Foster, William J

    2011-07-20

    When a patient suffers a retinal detachment and surgery is delayed, it is known clinically that bilaterally patching the patient may allow the retina to partially reattach or "settle." Although this procedure has been performed since the 1860s, there is still debate as to how such a maneuver facilitates the reattachment of the retina. Finite element calculations using commercially available analysis software are used to elucidate the influence of reduction in eye movement caused by bilateral patching on the flow of subretinal fluid in a physical model of retinal detachment. It was found that by coupling fluid mechanics with structural mechanics, a physically consistent explanation of increased retinal detachment with eye movements can be found in the case of traction on the retinal hole. Large eye movements increase vitreous traction and detachment forces on the edge of the retinal hole, creating a subretinal vacuum and facilitating increased subretinal fluid. Alternative models, in which intraocular fluid flow is redirected into the subretinal space, are not consistent with these simulations. The results of these simulations explain the physical principles behind bilateral patching and provide insight that can be used clinically. In particular, as is known clinically, bilateral patching may facilitate a decrease in the height of a retinal detachment. The results described here provide a description of a physical mechanism underlying this technique. The findings of this study may aid in deciding whether to bilaterally patch patients and in counseling patients on pre- and postoperative care.

  8. Measuring the Variations of the Apparent Settling Velocity for Fine Particles

    DEFF Research Database (Denmark)

    Larsen, Torben

    2000-01-01

    This note establishes the fact that the settling velocity for fine flocculent particles in flowing aquatic systems vary considerably and the settling velocity should therefore be understood as a variable which varies temporally and spatially in the flow field. In the mathematical formulation...

  9. Sensitivity analysis of the secondary settling tank double-exponential function model

    NARCIS (Netherlands)

    Abusam, A.; Keesman, K.J.

    2002-01-01

    The secondary settling tank plays a very crucial role in achieving the very strict effluent standards of wastewater treatment plants. To investigate the ability of the widely used secondary settling tank model, the double-exponential model, to predict the dynamic behavior, a factorial sensitivity an

  10. The effect of dust settling on the appearance of protoplanetary disks

    NARCIS (Netherlands)

    Dullemond, C.P.; Dominik, C.

    2004-01-01

    We analyze how the process of dust settling affects the spectral energy distribution and optical appearance of protoplanetary disks. Using simple analytic estimates on the one hand, and detailed 1+1-D models on the other hand, we show that, while the time scale for settling down to the equator may e

  11. Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks

    NARCIS (Netherlands)

    Abusam, A.; Keesman, K.J.

    2009-01-01

    The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In act

  12. 45 CFR 2554.48 - Can the administrative complaint be settled voluntarily?

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Can the administrative complaint be settled voluntarily? 2554.48 Section 2554.48 Public Welfare Regulations Relating to Public Welfare (Continued... Appeals § 2554.48 Can the administrative complaint be settled voluntarily? (a) Parties may make offers of...

  13. The effect of the ammonium ion on activated-sludge settling properties

    DEFF Research Database (Denmark)

    Novak, John Thomas

    2001-01-01

    by addition of sodium or ammonium, the interfacial settling velocity decreased, although the greatest drop was in the reactor containing ammonium. When addition of the nitrification inhibitor was stopped, rapid recovery of nitrification occurred but the settling properties improved more slowly. It seemed...

  14. 5 CFR 919.635 - May the OPM settle a debarment or suspension action?

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false May the OPM settle a debarment or suspension action? 919.635 Section 919.635 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED... Principles Relating to Suspension and Debarment Actions § 919.635 May the OPM settle a debarment...

  15. Experimental analysis of turbulence effect in settling velocity of suspended sediments

    Directory of Open Access Journals (Sweden)

    H. Salinas–Tapia

    2008-01-01

    Full Text Available Settling velocities of sediment particles for different size ranges were measured in this work using PIV with the help of discriminatory filters. An experimental channel 10x15 cm cross section was used in order to obtain two set of turbulent characteristics corresponding with two different flow rates. The purpose was to analyze the effect of turbulence on the solids settling velocity. The technique allowed us to measure the individual settling velocity of the particles and the flow velocity field of the fluid. Capture and image analysis was performed with digital cameras (CCD using the software Sharp–provision PIV and the statistical cross correlation technique. Results showed that settling velocity of particles is affected by turbulence which enhances the fluid drag coefficient. Physical explanation of this phenomenon is related with the magnitude of the vertical fluctuating velocity of the fluid. However, more research is needed in order to define settling velocity formulas that takes into account this effect

  16. CARBON REMOVAL FROM METALLIC SILICON BY CARBIDE SETTLING FOR SOLAR GRADE SILICON PRODUCTION

    Directory of Open Access Journals (Sweden)

    Tiago Ramos Ribeiro

    2015-03-01

    Full Text Available The use of solar energy is growing sharply in the past years. The most used material for solar cells is high-purity silicon produced by refining low-purity silicon. With the increasing demand for photovoltaic components, new refining processes have been investigated. Carbon is one of the impurities to be removed and one possible removing technique is based on the settling of silicon carbide particles. Settling tests were carried out at 1,500°C during one and six hours. Results show that differences in settling time do not affect carbon removal significantly and that the carbon contents after settling are still higher than that required by standards for solar grade silicon (43 ppm. Results from this work and from literature show that settling is not a feasible processing step for carbon removal to the level needed for photovoltaic applications.

  17. Microthrix parvicella abundance associates with activated sludge settling velocity and rheology - Quantifying and modelling filamentous bulking

    DEFF Research Database (Denmark)

    Wágner, Dorottya Sarolta; Ramin, Elham; Szabo, Peter;

    2015-01-01

    The objective of this work is to identify relevant settling velocity and rheology model parameters and to assess the underlying filamentous microbial community characteristics that can influence the solids mixing and transport in secondary settling tanks. Parameter values for hindered, transient...... viscometer. Quantitative fluorescence in-situ hybridisation (qFISH) analysis, targeting Microthrix parvicella and phylum Chloroflexi, was used. This study finds that M. parvicella - predominantly residing inside the microbial flocs in our samples - can significantly influence secondary settling through...... and compression settling velocity functions were estimated by carrying out biweekly batch settling tests using a novel column setup through a four-month long measurement campaign. To estimate viscosity model parameters, rheological experiments were carried out on the same sludge sample using a rotational...

  18. Unstable $m=1$ modes of counter-rotating Keplerian discs

    CERN Document Server

    Gulati, Mamta; Sridhar, S

    2012-01-01

    We study the linear $m=1$ counter-rotating instability in a two-component, nearly Keplerian disc. Our goal is to understand these \\emph{slow} modes in discs orbiting massive black holes in galactic nuclei. They are of interest not only because they are of large spatial scale--and can hence dominate observations--but also because they can be growing modes that are readily excited by accretion events. Self-gravity being nonlocal, the eigenvalue problem results in a pair of coupled integral equations, which we derive for a two-component softened gravity disc. We solve this integral eigenvalue problem numerically for various values of mass fraction in the counter-rotating component. The eigenvalues are in general complex, being real only in the absence of the counter-rotating component, or imaginary when both components have identical surface density profiles. Our main results are as follows: (i) the pattern speed appears to be non negative, with the growth (or damping) rate being larger for larger values of the ...

  19. The conformational flexibility of the antibiotic virginiamycin M(1).

    Science.gov (United States)

    Dang, Jason; Metzger, Robert P; Brownlee, Robert T C; Ng, Chai Ann; Bergdahl, Mikael; Separovic, Frances

    2005-07-01

    The antibiotic virginiamycin is a combination of two molecules, virginiamycin M(1) (VM1) and virginiamycin S(1) (VS1) or analogues, which function synergistically by binding to bacterial ribosomes and inhibiting bacterial protein synthesis. Both VM1 and VS1 dissolve poorly in water and are soluble in more hydrophobic solvents. We have recently reported that the 3D conformation of VM1 in CDCl(3) solution differs markedly from the conformation bound to a VM1 binding enzyme and to 50S ribosomes as found by X-ray crystallographic studies. We now report the results of further NMR studies and subsequent molecular modeling of VM1 dissolved in CD(3)CN/H(2)O and compare the structure with that in CD(3)OD and CDCl(3). The conformations of VM1 in CD(3)CN/H(2)O, CD(3)OD and CDCl(3) differ substantially from one another and from the bound form, with the aqueous form most like the bound structure. We propose that the flexibility of the VM1 molecule in response to environmental conditions contributes to its effectiveness as an antibiotic.

  20. The m=1 amplituhedron and cyclic hyperplane arrangements

    CERN Document Server

    Karp, Steven N

    2016-01-01

    The (tree) amplituhedron A(n,k,m) is the image in the Grassmannian Gr(k,k+m) of the totally nonnegative part of Gr(k,n), under a (map induced by a) linear map which is totally positive. It was introduced by Arkani-Hamed and Trnka in 2013 in order to give a geometric basis for the computation of scattering amplitudes in N=4 supersymmetric Yang-Mills theory. When k+m=n, the amplituhedron is isomorphic to the totally nonnegative Grassmannian, and when k=1, the amplituhedron is a cyclic polytope. While the case m=4 is most relevant to physics, the amplituhedron is an interesting mathematical object for any m. In this paper we study it in the case m=1. We start by taking an orthogonal point of view and define a related "B-amplituhedron" B(n,k,m), which we show is isomorphic to A(n,k,m). We use this reformulation to describe the amplituhedron in terms of sign variation. We then give a cell decomposition of the amplituhedron A(n,k,1) using the images of a collection of distinguished cells of the totally nonnegative ...

  1. Abundances of Planetary Nebula M1-42

    CERN Document Server

    Pottasch, S R; Roellig, T L

    2007-01-01

    The spectra of the planetary nebula M1-42 is reanalysed using spectral measurements made in the mid-infrared with the Spitzer Space Telescope. The aim is to determine the chemical composition of this object. We also make use of ISO, IUE and ground based spectra. Abundances determined from the mid- and far-infrared lines, which are insensitive to electron temperature, are used as the basis for the determination of the composition, which are found to substantially differ from earlier results. High values of neon, argon and sulfur are found. They are higher than in other PN, with the exception of NGC6153, a nebula of very similar abundances. The high values of helium and nitrogen found indicate that the second dredge-up and hot bottom burning has occurred in the course of evolution and that the central star was originally more massive than 4Msun. The present temperature and luminosity of the central star is determined and at first sight may be inconsistent with such a high mass.

  2. Thermoelectric waste heat recovery from an M1 Abrams tank

    Science.gov (United States)

    Stokes, C. David; Thomas, Peter M.; Baldasaro, Nicholas G.; Mantini, Michael J.; Venkatasubramanian, Rama; Barton, Michael D.; Cardine, Christopher V.; Walker, Grayson W.

    2012-06-01

    The addition of advanced sensors, targeting systems and electronic countermeasures to military vehicles has created a strategic need for additional electric power. By incorporating a thermoelectric (TE) waste heat recovery system to convert available exhaust heat to electricity, increased electric power needs can be met without reducing the energy efficiency of the vehicle. This approach allows existing vehicles to be upgraded without requiring a complete re-design of the engine and powertrain to support the integration of advanced electronic sensors and systems that keep the performance at the state of the art level. RTI has partnered with General Dynamics Land Systems and Creare, Inc. under an Army Research Lab program to develop a thermoelectric exhaust waste heat recovery system for the M1 Abrams tank. We have designed a reduced-scale system that was retrofitted to the tank and generated 80W of electric power on the vehicle operating on a test track by capturing a portion of the exhaust heat from the Honeywell/Lycoming AGT-1500 gas turbine engine.

  3. THE EPOCH OF DISK SETTLING: z {approx} 1 TO NOW

    Energy Technology Data Exchange (ETDEWEB)

    Kassin, Susan A.; Gardner, Jonathan P. [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Weiner, Benjamin J.; Willmer, C. N. A. [Steward Observatory, University of Arizona, Tucson, AZ (United States); Faber, S. M.; Guhathakurta, Puragra; Koo, David C. [UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Coil, Alison L. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Cooper, Michael C. [Center for Galaxy Evolution, Department of Physics and Astronomy, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Devriendt, Julien [Department of Physics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom); Dutton, Aaron A. [Max Planck Institute for Astronomy, Koenigstuhl 17, D-69117 Heidelberg (Germany); Metevier, A. J. [Department of Physics and Astronomy, Sonoma State University, 1801 East Cotati Avenue, Rohnert Park, CA 94928 (United States); Noeske, Kai G. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Primack, Joel R., E-mail: susan.kassin@nasa.gov [Department of Physics, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2012-10-20

    We present evidence from a sample of 544 galaxies from the DEEP2 Survey for evolution of the internal kinematics of blue galaxies with stellar masses ranging 8.0 < log M {sub *}(M {sub Sun }) < 10.7 over 0.2 < z < 1.2. DEEP2 provides galaxy spectra and Hubble imaging from which we measure emission-line kinematics and galaxy inclinations, respectively. Our large sample allows us to overcome scatter intrinsic to galaxy properties in order to examine trends in kinematics. We find that at a fixed stellar mass, galaxies systematically decrease in disordered motions and increase in rotation velocity and potential well depth with time. Massive galaxies are the most well ordered at all times examined, with higher rotation velocities and less disordered motions than less massive galaxies. We quantify disordered motions with an integrated gas velocity dispersion corrected for beam smearing ({sigma} {sub g}). It is unlike the typical pressure-supported velocity dispersion measured for early type galaxies and galaxy bulges. Because both seeing and the width of our spectral slits comprise a significant fraction of the galaxy sizes, {sigma} {sub g} integrates over velocity gradients on large scales which can correspond to non-ordered gas kinematics. We compile measurements of galaxy kinematics from the literature over 1.2 < z < 3.8 and do not find any trends with redshift, likely for the most part, because these data sets are biased toward the most highly star-forming systems. In summary, over the last {approx}8 billion years since z = 1.2, blue galaxies evolve from disordered to ordered systems as they settle to become the rotation-dominated disk galaxies observed in the universe today, with the most massive galaxies being the most evolved at any time.

  4. A BIOPHYSIOCHEMICAL ANALYSIS OF SETTLED LIVESTOCK AND POULTRY HOUSING DUSTS

    Directory of Open Access Journals (Sweden)

    Carresse Gerald

    2014-01-01

    Full Text Available The levels and composition of agricultural dusts are influenced by animal species, production strategy, housing type and ventilation efficiency. Agricultural dust within animal houses is complex and consists of feed particles, microbes and their products, dander, fecal matter, gases, metals and other organic and inorganic components. Livestock and poultry production facilities may be categorized as confinement, semi-confinement or pasture-based. Characterization of animal husbandry building dust will provide insight into understanding exposures experienced by animals, workers and farm visitors. The goal was to characterize biophysiochemical features of livestock dusts from swine, small ruminant, equine, poultry and cattle husbandry units. Settled dust samples were collected from livestock and poultry housing units at the University Farm and other livestock farms across the state. Morphological features were determined by electron microscopy and gravimetry. Biochemical evaluation consisted of pH determination and trace metal detection via mass spectrometry. Biological assessment centered on bacterial characterization via selective media, DNA analysis and endotoxin quantitation. Morphological analyses revealed higher levels of respirable and thoracic particles in poultry, swine, small ruminant and equine units compared to the dairy unit (p<0.01. Dusts were slightly acidic with the exception of the NCAT small ruminant unit (p<0.05. Dust endotoxin levels were consistent and bacterial species detected include Listeria and Escherichia coli. These findings suggest animal husbandry buildings harbor higher levels of smaller respirable and thoracic dust particles compared to inhalable particles. This information may be helpful in understanding dust exposures experienced by animals, farmers and agricultural workers.

  5. Detailed spatio-temporal solids concentration profiling during batch settling of activated sludge using a radiotracer.

    Science.gov (United States)

    De Clercq, Jeriffa; Jacobs, Filip; Kinnear, David J; Nopens, Ingmar; Dierckx, Rudi A; Defrancq, Jacques; Vanrolleghem, Peter A

    2005-05-01

    In building and tuning good settling models for secondary clarifiers of wastewater treatment plants, there is a need for measured continuous solids concentration profiles during batch settling. Conventional measuring techniques have difficulties in recording this kind of data, either because they are invasive, or because of the low solids concentration and/or solids density of activated sludge. This paper investigates a novel non-invasive measurement technique borrowed from nuclear medicine, using a solids radiotracer and gamma cameras, to obtain solids concentration profiles during the batch settling of activated sludge, in a pilot-scale column with a height of 1m. The technique does not disturb the settling process, does not alter the settling characteristics, gives profiles every minute and every few millimeters, and is capable of measuring in a range of 0-25 g/l with high accuracy. Dynamic solids concentration profile measurements were performed for sludges of different wastewater treatment plants, and at different initial concentrations. The results show a quantitative representation of the settling process, and reveal hindered and compression settling.

  6. PCB decline in settling particles and benthic recycling of PCBs and PAHs in Lake Superior

    Energy Technology Data Exchange (ETDEWEB)

    Jeremiason, J.D. [Rutgers Univ., New Brunswick, NJ (United States). Dept. of Environmental Sciences]|[Chesapeake Biological Lab., Solomons, MD (United States); Eisenreich, S.J. [Rutgers Univ., New Brunswick, NJ (United States). Dept. of Environmental Sciences; Baker, J.E. [Chesapeake Biological Lab., Solomons, MD (United States); Eadie, B.J. [NOAA, Ann Arbor, MI (United States). Great Lakes Environmental Research Lab.

    1998-11-01

    Sediment traps were deployed at fives sites in Lake Superior at multiple depths during lake stratification in 1987 and 1991. Mass, organic carbon, PCB, and PAH fluxes were determined. PCB concentrations on settling solids declined from 1984 to 1991 with a first-order rate constant of 0.26 yr{sup {minus}1} similar to reported water column concentration decreases. Total PCB settling fluxes from the upper 35 m of water averaged 121 {+-} 40 ng/m{sup 2}{center_dot}d in 1987 and 48 {+-} 23 ng/m{sup 2}{center_dot}d in 1991. Settling fluxes are greater than reported wet and dry deposition fluxes and demonstrate the intense recycling of PCBs within the lake. A large fraction of the total Lake Superior water PCB burden is transported each year by settling particles to within 5 m of the lake bottom, but only 2--5% of settling PCBs accumulate in bottom sediments. Thus, most of the PCBs are recycled in the benthic region, possibly representing a major entry point for PCBs into higher trophic levels through the benthic food web. Benthic recycling of PAH compounds with three and four rings occurred, but a larger fraction of these settling PAHs accumulated in bottom sediments. No consistent temporal trends were observed in PAH concentrations on settling particles from 1984 to 1991.

  7. Effect of Dissolved Oxygen on Microbial Population and Settling of Dairy Activated Sludge

    Directory of Open Access Journals (Sweden)

    T. Subramani

    2014-12-01

    Full Text Available The study was carried out to identify and study the settling characteristics of the dairy activated sludge. The causes and the control measure for the sludge bulking were studied. The activated sludge was generated by running a batch reactor of capacity of 10 liters for a θC of 10 days. It was operated until steady state conditions were reached. pH, DO, MLSS and COD were taken as the parameters. The settling studies were carried out for different MLSS concentrations ranging from 2g/L to 20g/L. The addition of Chlorine was selected as the control measure and was added for various doses such as 1 ml, 2 ml and 3 ml of Bleaching powder solution (1 ml of Bleaching powder solution contains 0.515 mg of Chlorine. Settling curves between interface height and time were observed before and after the addition of the Chlorine. From the settling curve the limiting solids flux were obtained. After the addition of Chlorine, there was a considerable increase in the settling velocity that improves the settling nature of the sludge. Area of Secondary settling tank was calculated from the modified solids flux method.

  8. Modulation of Effects of Intermittent Theta Burst Stimulation Applied Over Primary Motor Cortex (M1) by Conditioning Stimulation of the Opposite M1

    Science.gov (United States)

    Ragert, Patrick; Camus, Mickael; Vandermeeren, Yves; Dimyan, Michael A.; Cohen, Leonardo G.

    2009-01-01

    The excitability of the human primary motor cortex (M1) as tested with transcranial magnetic stimulation (TMS) depends on its previous history of neural activity. Homeostatic plasticity might be one important physiological mechanism for the regulation of corticospinal excitability and synaptic plasticity. Although homeostatic plasticity has been demonstrated locally within M1, it is not known whether priming M1 could result in similar homeostatic effects in the homologous M1 of the opposite hemisphere. Here, we sought to determine whether down-regulating excitability (priming) in the right (R) M1 with 1-Hz repetitive transcranial magnetic stimulation (rTMS) changes the excitability-enhancing effect of intermittent theta burst stimulation (iTBS) applied over the homologous left (L) M1. Subjects were randomly allocated to one of four experimental groups in a sham-controlled parallel design with real or sham R M1 1-Hz TMS stimulation always preceding L M1 iTBS or sham by about 10 min. The primary outcome measure was corticospinal excitability in the L M1, as measured by recruitment curves (RCs). Secondary outcome measures included pinch force, simple reaction time, and tapping speed assessed in the right hand. The main finding of this study was that preconditioning R M1 with 1-Hz rTMS significantly decreased the excitability-enhancing effects of subsequent L M1 iTBS on RCs. Application of 1-Hz rTMS over R M1 alone and iTBS over L M1 alone resulted in increased RC in L M1 relative to sham interventions. The present findings are consistent with the hypothesis that homeostatic mechanisms operating across hemispheric boundaries contribute to regulate motor cortical function in the primary motor cortex. PMID:19474173

  9. Computational Fluid Dynamics Modelling of Hydraulics and Sedimentation in Process Reactors during Aeration Tank Settling

    DEFF Research Database (Denmark)

    Jensen, M.D.; Ingildsen, P.; Rasmussen, Michael R.;

    2006-01-01

    Aeration tank settling is a control method allowing settling in the process tank during highhydraulic load. The control method is patented. Aeration tank settling has been applied in several wastewater treatment plants using the present design of the process tanks. Some process tank designs...... haveshown to be more effective than others. To improve the design of less effective plants, computational fluiddynamics (CFD) modelling of hydraulics and sedimentation has been applied. This paper discusses theresults at one particular plant experiencing problems with partly short-circuiting of the inlet...... and outletcausing a disruption of the sludge blanket at the outlet and thereby reducing the retention of sludge in theprocess tank. The model has allowed us to establish a clear picture of the problems arising at the plantduring aeration tank settling. Secondly, several process tank design changes have been...

  10. Trade-off between Settling Time and Jitter in Phase Locked Loop

    CERN Document Server

    Paliwal, Pallavi; Gupta, Shalabh

    2012-01-01

    Most PLL architectures have inherent trade-off between settling time and jitter. This trade-off is ignored by commonly used Figure of Merit (FoM) for PLL, which considers only jitter and power for benchmarking PLL performance. This work proposes new Figure of Merit for PLL, which considers settling time also as performance parameter, along with jitter and power. In this work, trade-off between settling time and jitter is analyzed in linear/non-linear/hybrid PLLs, theoretically and with behavioral simulations. Then, based on settling time vs. jitter relation obtained, currently used Figure of Merit for PLL is modified to consider all important specifications i.e. lock time, power and jitter.

  11. Track Settling Control System to Reduce Residual Vibration during Track Seek of Magnetic Disk Drives

    National Research Council Canada - National Science Library

    Nakagawa, Shinsuke; Yamaguchi, Takashi

    2003-01-01

    .... These mode switching controllers provide fast access and accurate positioning. The requirement of faster seeking in magnetic disk drives propagates residual vibration during settling due to the mechanical resonance of the positioning system...

  12. Dynamic modeling of sludge compaction and consolidation processes in wastewater secondary settling tanks.

    Science.gov (United States)

    Abusam, A; Keesman, K J

    2009-01-01

    The double exponential settling model is the widely accepted model for wastewater secondary settling tanks. However, this model does not estimate accurately solids concentrations in the settler underflow stream, mainly because sludge compression and consolidation processes are not considered. In activated sludge systems, accurate estimation of the solids in the underflow stream will facilitate the calibration process and can lead to correct estimates of particularly kinetic parameters related to biomass growth. Using principles of compaction and consolidation, as in soil mechanics, a dynamic model of the sludge consolidation processes taking place in the secondary settling tanks is developed and incorporated to the commonly used double exponential settling model. The modified double exponential model is calibrated and validated using data obtained from a full-scale wastewater treatment plant. Good agreement between predicted and measured data confirmed the validity of the modified model.

  13. Multiphase flow modelling of volcanic ash particle settling in water using adaptive unstructured meshes

    OpenAIRE

    Jacobs, C.T.; Collins, G S; M. D. Piggott; S. C. Kramer; Wilson, C.R.G.

    2013-01-01

    Small-scale experiments of volcanic ash particle settling in water have demonstrated that ash particles can either settle slowly and individually, or rapidly and collectively as a gravitationally unstable ash-laden plume. This has important implications for the emplacement of tephra deposits on the seabed. Numerical modelling has the potential to extend the results of laboratory experiments to larger scales and explore the conditions under which plumes may form and persist, but many existing ...

  14. Predicting the settling velocity of flocs formed in water treatment using multiple fractal dimensions.

    Science.gov (United States)

    Vahedi, Arman; Gorczyca, Beata

    2012-09-01

    Here we introduce a distribution of floc fractal dimensions as opposed to a single fractal dimension value into the floc settling velocity model developed in earlier studies. The distribution of fractal dimensions for a single floc size was assumed to cover a range from 1.9 to 3.0. This range was selected based on the theoretically determined fractal dimensions for diffusion-limited and cluster-cluster aggregation. These two aggregation mechanisms are involved in the formation of the lime softening flocs analyzed in this study. Fractal dimensions were generated under the assumption that a floc can have any value of normally distributed fractal dimensions ranging from 1.9-3.0. A range of settling velocities for a single floc size was calculated based on the distribution of fractal dimensions. The assumption of multiple fractal dimensions for a single floc size resulted in a non-unique relationship between the floc size and the floc settling velocity, i.e., several different settling velocities were calculated for one floc size. The settling velocities calculated according to the model ranged from 0 to 10 mm/s (average 2.22 mm/s) for the majority of flocs in the size range of 1-250 μm (average 125 μm). The experimentally measured settling velocities of flocs ranged from 0.1 to 7.1 mm/s (average 2.37 mm/s) for the flocs with equivalent diameters from 10 μm to 260 μm (average 124 μm). Experimentally determined floc settling velocities were predicted well by the floc settling model incorporating distributions of floc fractal dimensions calculated based on the knowledge of the mechanisms of aggregation, i.e., cluster-cluster aggregation and diffusion-limited aggregation.

  15. Effects of heavy-element settling on solar neutrino fluxes and interior structure

    Science.gov (United States)

    Proffitt, Charles R.

    1994-01-01

    We consider the effects of gravitational settling of both He and heavier elements on the predicted solar neutrino fluxes and interior sound speed and density profiles. We find that while the structural changes that result from the inclusion of both He and heavy-element settling are only slightly larger than the changes resulting from the inclusion of He settling alone, the additional increases in expected neutrino fluxes are of comparable size. Our preferred model with both He and heavy-element settling has neutrino count rates of 9.0 SNU for Cl-37 detectors and 137 SNU for Ga-71 detectors, as compared to 7.1 and 127 SNU for a comparable model without any diffusive separation, or 8.0 and 132 SNU for a model that includes He settling alone. We suggest that the correction factors by which the predicted neutrino fluxes of solar models calculated without including the effects of diffusion should be multiplied are 1.25 +/- 0.08 for Cl detectors, 1.07 +/- 0.02 for Ga detectors, and 1.28 +/- 0.09 for the B-8 flux (1 sigma errors). Comparison of internal sound speed and density profiles strongly suggests that the additional changes in calculated p-mode oscillation frequencies due to the inclusion of heavy-element settling will be small compared to the changes that result from He settling alone, especially for the higher degree modes. All models with diffusive separation give much better agreement with the observed depth of the convection zone than do nondiffusive models. The model that includes both He and heavy-element settling requires an initial He mass fraction Y = 0.280 and has a surface He abundance of Y = 0.251 at the solar age.

  16. The TNM 8 M1b and M1c classification for non-small cell lung cancer in a cohort of patients with brain metastases.

    Science.gov (United States)

    Nieder, C; Hintz, M; Oehlke, O; Bilger, A; Grosu, A L

    2017-09-01

    According to the recent TNM 8 classification, patients with metastatic non-small cell lung cancer (NSCLC) and single extrathoracic metastasis should be classified as stage M1b, while those with 2 or more metastases comprise stage M1c. The purpose of this study was to analyze the impact of this classification in patients with brain metastases. This retrospective study included 172 patients treated with individualized approaches. Actuarial survival was calculated. Uni- and multivariate analyses were performed. Thirty patients (17%) were staged as M1b. Those with squamous cell cancer were more likely to harbor M1b disease (29%, adenocarcinoma 14%, other histology 17%, p = 0.16). Median survival was 5.4 months (8.0 months in case of M1b disease and 4.5 months in case of M1c disease, p = 0.001). Multivariate analysis confirmed the role of M1b stage. M1b patients managed with upfront surgery or radiosurgery had significantly longer median survival than those who received whole-brain irradiation (21.0 vs. 3.5 months, p = 0.0001) and the potential to survive beyond 5 years. We found the M1b classification to provide clinically relevant information. The multivariate analysis suggested that patients with M1b disease, better performance status and younger age have better survival.

  17. Settling into an Increasingly Hostile World: The Rapidly Closing “Recruitment Window” for Corals

    Science.gov (United States)

    Arnold, Suzanne N.; Steneck, Robert S.

    2011-01-01

    Free space is necessary for larval recruitment in all marine benthic communities. Settling corals, with limited energy to invest in competitive interactions, are particularly vulnerable during settlement into well-developed coral reef communities. This situation may be exacerbated for corals settling into coral-depauperate reefs where succession in nursery microhabitats moves rapidly toward heterotrophic organisms inhospitable to settling corals. To study effects of benthic organisms (at millimeter to centimeter scales) on newly settled corals and their survivorship we deployed terra-cotta coral settlement plates at 10 m depth on the Mesoamerican Barrier Reef in Belize and monitored them for 38 mo. During the second and third years, annual recruitment rates declined by over 50% from the previous year. Invertebrate crusts (primarily sponges) were absent at the start of the experiment but increased in abundance annually from 39, 60, to 73% of the plate undersides by year three. Subsequently, substrates hospitable to coral recruitment, including crustose coralline algae, biofilmed terra-cotta and polychaete tubes, declined. With succession, substrates upon which spat settled shifted toward organisms inimical to survivorship. Over 50% of spat mortality was due to overgrowth by sponges alone. This result suggests that when a disturbance creates primary substrate a “recruitment window” for settling corals exists from approximately 9 to 14 mo following the disturbance. During the window, early-succession, facilitating species are most abundant. The window closes as organisms hostile to coral settlement and survivorship overgrow nursery microhabitats. PMID:22194883

  18. Settling into an increasingly hostile world: the rapidly closing "recruitment window" for corals.

    Directory of Open Access Journals (Sweden)

    Suzanne N Arnold

    Full Text Available Free space is necessary for larval recruitment in all marine benthic communities. Settling corals, with limited energy to invest in competitive interactions, are particularly vulnerable during settlement into well-developed coral reef communities. This situation may be exacerbated for corals settling into coral-depauperate reefs where succession in nursery microhabitats moves rapidly toward heterotrophic organisms inhospitable to settling corals. To study effects of benthic organisms (at millimeter to centimeter scales on newly settled corals and their survivorship we deployed terra-cotta coral settlement plates at 10 m depth on the Mesoamerican Barrier Reef in Belize and monitored them for 38 mo. During the second and third years, annual recruitment rates declined by over 50% from the previous year. Invertebrate crusts (primarily sponges were absent at the start of the experiment but increased in abundance annually from 39, 60, to 73% of the plate undersides by year three. Subsequently, substrates hospitable to coral recruitment, including crustose coralline algae, biofilmed terra-cotta and polychaete tubes, declined. With succession, substrates upon which spat settled shifted toward organisms inimical to survivorship. Over 50% of spat mortality was due to overgrowth by sponges alone. This result suggests that when a disturbance creates primary substrate a "recruitment window" for settling corals exists from approximately 9 to 14 mo following the disturbance. During the window, early-succession, facilitating species are most abundant. The window closes as organisms hostile to coral settlement and survivorship overgrow nursery microhabitats.

  19. Formulation of the Settling Velocity of Small Particles Initially Situated inside an Inclined Vortex

    Directory of Open Access Journals (Sweden)

    Urbano Sánchez

    2016-01-01

    Full Text Available Both the estimation of the time that small heavy particles remain inside a 3D vortex and the estimation of the average settling velocity of those particles are some important features in many practical situations. Previous works focused on the case of a horizontal 2D vortex. In this paper, we simulate the dynamics of heavy particles initially situated inside a three-dimensional vortex obtaining a formula for their average settling velocity. In a previous paper we obtained the trajectories of the particles and a formula that provides the time that they need to escape, Te⁎. This work simulates and analyses the escape process, and its main result is the obtaining, from numerical simulation, of a theoretical formulation of the average settling velocity Vz⁎ and its relationship with the elapsed time. We prove that the permanence time is of the order of dp⁎-10 (with dp⁎ particle diameter and that the average settling velocity is of the order of Te⁎-1/5 for sufficiently small particles. Some applications of the settling velocity formula developed in this work would be the design of mixture devices, the design of particle separation devices, and the prediction of the settling of pollutant particles, seeds, and pollen.

  20. Negative effect of dissolved organic compounds on settling behavior of synthetic monominerals in red mud

    Institute of Scientific and Technical Information of China (English)

    王梦; 胡慧萍; 刘锦伟; 陈启元

    2016-01-01

    Hydration grossular and hematite monominerals were synthesized. The effects of dissolved organic compounds (including sodium formate, sodium acetate, sodium oxalate, sodium salicylate or disodium phthalate) on the settling performance of hydration grossular or hematite slurries were studied. The settling of the slurries was also investigated with the addition of sodium polyacrylate (PAAS) or hydroxamated polyacrylamide flocculant (HCPAM). The adsorption mechanism of organic compounds on monominerals surfaces was studied by FT-IR and XPS, respectively. A deterioration in settling is observed in order of disodium phthalate>sodium salicylate>sodium oxalate>sodium formate (or sodium acetate). Moreover, PAAS can efficiently eliminate the negative effects of organic compounds on the settling performance of the hydration grossular slurry. HCPAM can efficiently eliminate the negative effects of sodium formate, sodium acetate and sodium oxalate on the settling performance of the hematite slurry, but it only partially improves the settling performance of hematite slurry containing sodium salicylate or disodium phthalate. FT-IR and XPS results show that organic compounds are physically adsorbed on hydration grossular surface, and chemisorptions of organic compounds occur on hematite surface with a bidentate chelating complex.

  1. Turbulent particle transport in streams: can exponential settling be reconciled with fluid mechanics?

    Science.gov (United States)

    McNair, James N; Newbold, J Denis

    2012-05-07

    Most ecological studies of particle transport in streams that focus on fine particulate organic matter or benthic invertebrates use the Exponential Settling Model (ESM) to characterize the longitudinal pattern of particle settling on the bed. The ESM predicts that if particles are released into a stream, the proportion that have not yet settled will decline exponentially with transport time or distance and will be independent of the release elevation above the bed. To date, no credible basis in fluid mechanics has been established for this model, nor has it been rigorously tested against more-mechanistic alternative models. One alternative is the Local Exchange Model (LEM), which is a stochastic advection-diffusion model that includes both longitudinal and vertical spatial dimensions and is based on classical fluid mechanics. The LEM predicts that particle settling will be non-exponential in the near field but will become exponential in the far field, providing a new theoretical justification for far-field exponential settling that is based on plausible fluid mechanics. We review properties of the ESM and LEM and compare these with available empirical evidence. Most evidence supports the prediction of both models that settling will be exponential in the far field but contradicts the ESM's prediction that a single exponential distribution will hold for all transport times and distances.

  2. Experimental Conditions: SE37_S18_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available opes SE37_S18 PSEUDO: Unlabeled and labeled Medicago samples for metabolite annotation using ShiftedIonsFind...17_M1), and for Medicago samples labeled by 13C (S05_M1), 15N (S07_M1), 28O (S10_M1), and 34S (S13_M1) are used. SE37_DS4 Labeled peak search by ShiftedIonsFinder ...

  3. Concentration-driven models revisited: towards a unified framework to model settling tanks in water resource recovery facilities.

    Science.gov (United States)

    Torfs, Elena; Martí, M Carmen; Locatelli, Florent; Balemans, Sophie; Bürger, Raimund; Diehl, Stefan; Laurent, Julien; Vanrolleghem, Peter A; François, Pierre; Nopens, Ingmar

    2017-02-01

    A new perspective on the modelling of settling behaviour in water resource recovery facilities is introduced. The ultimate goal is to describe in a unified way the processes taking place both in primary settling tanks (PSTs) and secondary settling tanks (SSTs) for a more detailed operation and control. First, experimental evidence is provided, pointing out distributed particle properties (such as size, shape, density, porosity, and flocculation state) as an important common source of distributed settling behaviour in different settling unit processes and throughout different settling regimes (discrete, hindered and compression settling). Subsequently, a unified model framework that considers several particle classes is proposed in order to describe distributions in settling behaviour as well as the effect of variations in particle properties on the settling process. The result is a set of partial differential equations (PDEs) that are valid from dilute concentrations, where they correspond to discrete settling, to concentrated suspensions, where they correspond to compression settling. Consequently, these PDEs model both PSTs and SSTs.

  4. On constitutive functions for hindered settling velocity in 1-D settler models: Selection of appropriate model structure.

    Science.gov (United States)

    Torfs, Elena; Balemans, Sophie; Locatelli, Florent; Diehl, Stefan; Bürger, Raimund; Laurent, Julien; François, Pierre; Nopens, Ingmar

    2017-03-01

    Advanced 1-D models for Secondary Settling Tanks (SSTs) explicitly account for several phenomena that influence the settling process (such as hindered settling and compression settling). For each of these phenomena a valid mathematical expression needs to be selected and its parameters calibrated to obtain a model that can be used for operation and control. This is, however, a challenging task as these phenomena may occur simultaneously. Therefore, the presented work evaluates several available expressions for hindered settling based on long-term batch settling data. Specific attention is paid to the behaviour of these hindered settling functions in the compression region in order to evaluate how the modelling of sludge compression is influenced by the choice of a certain hindered settling function. The analysis shows that the exponential hindered settling forms, which are most commonly used in traditional SST models, not only account for hindered settling but partly lump other phenomena (compression) as well. This makes them unsuitable for advanced 1-D models that explicitly include each phenomenon in a modular way. A power-law function is shown to be more appropriate to describe the hindered settling velocity in advanced 1-D SST models.

  5. Anti-CD47 Treatment Stimulates Phagocytosis of Glioblastoma by M1 and M2 Polarized Macrophages and Promotes M1 Polarized Macrophages In Vivo.

    Directory of Open Access Journals (Sweden)

    Michael Zhang

    Full Text Available Tumor-associated macrophages (TAMs represent an important cellular subset within the glioblastoma (WHO grade IV microenvironment and are a potential therapeutic target. TAMs display a continuum of different polarization states between antitumorigenic M1 and protumorigenic M2 phenotypes, with a lower M1/M2 ratio correlating with worse prognosis. Here, we investigated the effect of macrophage polarization on anti-CD47 antibody-mediated phagocytosis of human glioblastoma cells in vitro, as well as the effect of anti-CD47 on the distribution of M1 versus M2 macrophages within human glioblastoma cells grown in mouse xenografts. Bone marrow-derived mouse macrophages and peripheral blood-derived human macrophages were polarized in vitro toward M1 or M2 phenotypes and verified by flow cytometry. Primary human glioblastoma cell lines were offered as targets to mouse and human M1 or M2 polarized macrophages in vitro. The addition of an anti-CD47 monoclonal antibody led to enhanced tumor-cell phagocytosis by mouse and human M1 and M2 macrophages. In both cases, the anti-CD47-induced phagocytosis by M1 was more prominent than that for M2. Dissected tumors from human glioblastoma xenografted within NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice and treated with anti-CD47 showed a significant increase of M1 macrophages within the tumor. These data show that anti-CD47 treatment leads to enhanced tumor cell phagocytosis by both M1 and M2 macrophage subtypes with a higher phagocytosis rate by M1 macrophages. Furthermore, these data demonstrate that anti-CD47 treatment alone can shift the phenotype of macrophages toward the M1 subtype in vivo.

  6. Anti-CD47 Treatment Stimulates Phagocytosis of Glioblastoma by M1 and M2 Polarized Macrophages and Promotes M1 Polarized Macrophages In Vivo

    Science.gov (United States)

    Kahn, Suzana A.; Azad, Tej D.; Gholamin, Sharareh; Xu, Chelsea Y.; Liu, Jie; Achrol, Achal S.; Richard, Chase; Sommerkamp, Pia; Schoen, Matthew Kenneth; McCracken, Melissa N.; Majeti, Ravi; Weissman, Irving; Mitra, Siddhartha S.; Cheshier, Samuel H.

    2016-01-01

    Tumor-associated macrophages (TAMs) represent an important cellular subset within the glioblastoma (WHO grade IV) microenvironment and are a potential therapeutic target. TAMs display a continuum of different polarization states between antitumorigenic M1 and protumorigenic M2 phenotypes, with a lower M1/M2 ratio correlating with worse prognosis. Here, we investigated the effect of macrophage polarization on anti-CD47 antibody-mediated phagocytosis of human glioblastoma cells in vitro, as well as the effect of anti-CD47 on the distribution of M1 versus M2 macrophages within human glioblastoma cells grown in mouse xenografts. Bone marrow-derived mouse macrophages and peripheral blood-derived human macrophages were polarized in vitro toward M1 or M2 phenotypes and verified by flow cytometry. Primary human glioblastoma cell lines were offered as targets to mouse and human M1 or M2 polarized macrophages in vitro. The addition of an anti-CD47 monoclonal antibody led to enhanced tumor-cell phagocytosis by mouse and human M1 and M2 macrophages. In both cases, the anti-CD47-induced phagocytosis by M1 was more prominent than that for M2. Dissected tumors from human glioblastoma xenografted within NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice and treated with anti-CD47 showed a significant increase of M1 macrophages within the tumor. These data show that anti-CD47 treatment leads to enhanced tumor cell phagocytosis by both M1 and M2 macrophage subtypes with a higher phagocytosis rate by M1 macrophages. Furthermore, these data demonstrate that anti-CD47 treatment alone can shift the phenotype of macrophages toward the M1 subtype in vivo. PMID:27092773

  7. Multiphase flow modelling of volcanic ash particle settling in water using adaptive unstructured meshes

    Science.gov (United States)

    Jacobs, C. T.; Collins, G. S.; Piggott, M. D.; Kramer, S. C.; Wilson, C. R. G.

    2013-02-01

    Small-scale experiments of volcanic ash particle settling in water have demonstrated that ash particles can either settle slowly and individually, or rapidly and collectively as a gravitationally unstable ash-laden plume. This has important implications for the emplacement of tephra deposits on the seabed. Numerical modelling has the potential to extend the results of laboratory experiments to larger scales and explore the conditions under which plumes may form and persist, but many existing models are computationally restricted by the fixed mesh approaches that they employ. In contrast, this paper presents a new multiphase flow model that uses an adaptive unstructured mesh approach. As a simulation progresses, the mesh is optimized to focus numerical resolution in areas important to the dynamics and decrease it where it is not needed, thereby potentially reducing computational requirements. Model verification is performed using the method of manufactured solutions, which shows the correct solution convergence rates. Model validation and application considers 2-D simulations of plume formation in a water tank which replicate published laboratory experiments. The numerically predicted settling velocities for both individual particles and plumes, as well as instability behaviour, agree well with experimental data and observations. Plume settling is clearly hindered by the presence of a salinity gradient, and its influence must therefore be taken into account when considering particles in bodies of saline water. Furthermore, individual particles settle in the laminar flow regime while plume settling is shown (by plume Reynolds numbers greater than unity) to be in the turbulent flow regime, which has a significant impact on entrainment and settling rates. Mesh adaptivity maintains solution accuracy while providing a substantial reduction in computational requirements when compared to the same simulation performed using a fixed mesh, highlighting the benefits of an

  8. Organic Geochemical Characteristics of Time—Series Settling Particles in Northern SOuth China Sea and Their Implications

    Institute of Scientific and Technical Information of China (English)

    陈建芳; HOW-KINWONG; 等

    1998-01-01

    Organic carbon,total nitrogen,amino acids,sugars,and chlorophyll were deter mined in <1mm fractions of the samples collected by successive large aperture time-series sediment traps(Honjo-Mark VI) in northern South China Sea during September 1987 to October 1988,The ratio of C/N and the relative abundance of amino acids and sugars show that organic matter in the settling particles from northern South China Sea is derived mainly from marine plantkon(esecially phytoplankton),The organic carbon fluxes in our sediment traps are lower than those in other sediment traps.But the relative contents of Corg/total particulate matter are generally similar to those in the Panama Basin,Arabian Sea and Subarctic Pacific.It is suggested that monsoon-caused changes of physical and chemical conditions in the upper euphotic layer would control the fluxes of organic matter as well as its composition and transport in northern South China Sea.

  9. Biofilm effects on size gradation, drag coefficient and settling velocity of sediment particles

    Institute of Scientific and Technical Information of China (English)

    Qian-qian SHANG; Hong-wei FANG; Hui-ming ZHAO; Guo-jian HE; Zheng-hui CUI

    2014-01-01

    Sediment particles are often colonized by biofilm in a natural aquatic ecological system, especially in eutrophic water body. A series of laboratory experiments on particle size gradation, drag coefficient and settling velocity were conducted after natural sediment was colonized by biofilm for 5, 10, 15 and 20 days. Particle image acquisition, particle tracking techniques of Particle Image Velocimetry and Particle Tracking Velocimetry were utilized to analyze the changes of these properties. The experimental results indicate that the size gradation, the drag force exerted on bio-particles, and the settling velocity of bio-particles underwent significant change due to the growth of biofilm onto the sediment surface. The study proposes a characteristic particle size formula and a bio-particle settling velocity formula based on the regression of experiment results, that the settling velocity is only 50% to 60%as the single particle which has the same diameter and density. However, biofilm growth causes large particle which the settling velocities are approximately 10 times larger than that of primary particles. These results may be specifically used in the low energy reservoir or lake environment.

  10. Sludge settling processes in SBR-related sewage treatment plants according to the Biocos method.

    Science.gov (United States)

    Meusel, S; Englert, R

    2004-01-01

    This paper describes the investigations in a sedimentation and circulation reactor (SU-reactor) of a three-phase Biocos plant. The aim of these investigations was the determination of the temporal and depth-dependent distribution of suspended solid contents, as well as describing the sludge sedimentation curves. The calculated results reveal peculiarities of the Biocos method with regard to sedimentation processes. In the hydraulically uninterrupted (pre-)settling phase, a sludge level depth was observed, which remained constant over the reactor surface and increased linearly according to the sludge volume. The settling and the thickening processes of this phase corresponded to a large extent to the well-known settling test in a one-litre measuring cylinder. During the discharge phase, the investigated settling rate was overlaid by the surface loading rate and the sludge level changed depending on the difference between those two parameters. The solid distribution of the A-phase indicated a formation of functional zones, which were influenced by the surface loading. The formation was comparable to the formation of layers in secondary settling tanks with vertical flow. The concentration equalisation between the biological reactor and the SU-reactor proved to be problematic during the circulation phase, because a type of internal sludge circulation occurred in the SU-reactor. A permanent sludge recirculation seems to be highly recommendable.

  11. Exposure Assessment of Allergens and Metals in Settled Dust in French Nursery and Elementary Schools

    Directory of Open Access Journals (Sweden)

    Nuno Canha

    2015-11-01

    Full Text Available The aim of this study was to characterise the contamination in settled dust in French classrooms and to provide an overview of the influencing factors of dust contamination. Cat, dog and dust mite allergens and metals were measured in 51 classrooms at 17 schools. The concentrations of pet allergens in settled dust were generally low (mean value of 0.1 µg·g−1, with carpeted and rug-covered floors presenting higher dust and cat allergen concentrations. The highest metal loadings in dust were observed for manganese (Mn and copper (Cu, while the lead (Pb loadings were lower (16 ± 19 µg·m−2 and fell below the French guideline. Higher metal leachability was found for cadmium (Cd, Cu, Pb and strontium (Sr at values of approximately 80%, which suggest that, in cases of dust ingestion by children, a large proportion should be assimilated through the gastro-intestinal tract. The intra-classroom and intra-school variabilities of the metal concentrations in settled dust were lower than the variability between schools. Classrooms with tiled floors had higher Pb loadings than classrooms with wood or vinyl floors. In addition, wet cleaning less than once a week resulted in greater loadings of Cu and Pb in the settled dust. Lastly, enrichment factors showed that metals in settled dust of classrooms were not only from the contribution of the natural background concentrations in soils.

  12. Lattice Boltzmann Simulation of Healthy and Defective Red Blood Cell Settling in Blood Plasma.

    Science.gov (United States)

    Hashemi, Z; Rahnama, M; Jafari, S

    2016-05-01

    In this paper, an attempt has been made to study sedimentation of a red blood cell (RBC) in a plasma-filled tube numerically. Such behaviors are studied for a healthy and a defective cell which might be created due to human diseases, such as diabetes, sickle-cell anemia, and hereditary spherocytosis. Flow-induced deformation of RBC is obtained using finite-element method (FEM), while flow and fluid-membrane interaction are handled using lattice Boltzmann (LB) and immersed boundary methods (IBMs), respectively. The effects of RBC properties as well as its geometry and orientation on its sedimentation rate are investigated and discussed. The results show that decreasing frontal area of an RBC and/or increasing tube diameter results in a faster settling. Comparison of healthy and diabetic cells reveals that less cell deformability leads to slower settling. The simulation results show that the sicklelike and spherelike RBCs have lower settling velocity as compared with a biconcave discoid cell.

  13. Enhancement of settling tank capacity using a new type of tube settler.

    Science.gov (United States)

    Fujisaki, K

    2010-01-01

    The effectiveness of a newly developed lamellar settler was confirmed by onsite experiments. The device had inclined parallel plates arranged in a vertical direction in a settling tank. This vertical arrangement method enables many more plates to be set compared to the conventional horizontal arrangement. As an original and distinctive innovation, both the right and left edges of the plates were closed, for removing the clear water between the plates, The tube settler modules were installed in a final settling tank of a sewage treatment plant. Tests conducted over a 9 months period showed that the system operated successfully and under normal operation conditions, the new device could treat almost the same flow rate as that treated by a conventional tank, 5,000 m(3)/day. For storm water, the new tube settler was demonstrated to enhance the settling tank capacity by up to 3 times.

  14. On time discretizations for the simulation of the batch settling-compression process in one dimension.

    Science.gov (United States)

    Bürger, Raimund; Diehl, Stefan; Mejías, Camilo

    2016-01-01

    The main purpose of the recently introduced Bürger-Diehl simulation model for secondary settling tanks was to resolve spatial discretization problems when both hindered settling and the phenomena of compression and dispersion are included. Straightforward time integration unfortunately means long computational times. The next step in the development is to introduce and investigate time-integration methods for more efficient simulations, but where other aspects such as implementation complexity and robustness are equally considered. This is done for batch settling simulations. The key findings are partly a new time-discretization method and partly its comparison with other specially tailored and standard methods. Several advantages and disadvantages for each method are given. One conclusion is that the new linearly implicit method is easier to implement than another one (semi-implicit method), but less efficient based on two types of batch sedimentation tests.

  15. Theory for particle settling and shear-induced migration in thin-film liquid flow.

    Science.gov (United States)

    Cook, Benjamin P

    2008-10-01

    Particles suspended in a film flow can either settle out of the flow, remain well mixed, or even advance faster than the fluid, accumulating at the moving contact line. Recent experiments by Zhou et al. [Phys. Rev. Lett. 94, 117803 (2005)] have demonstrated that these three settling behaviors can be achieved by control of the average particle concentration phi and inclination angle theta . This work presents a theory for determining the settling behavior in the Stokes regime by calculating the depth profile of phi and the depth-averaged velocities of the liquid and particle phases. It is found that shear-induced particle fluxes can lead to an inversely stratified flow, in which the particles move on average faster than the liquid. The theory is directly compared to Zhou et al.'s experimental data, and the implications of stratification for lubrication-type models are also discussed.

  16. Characteristics of settling coral reef fish are related to recruitment timing and success.

    Directory of Open Access Journals (Sweden)

    Tauna L Rankin

    Full Text Available Many marine populations exhibit high variability in the recruitment of young into the population. While environmental cycles and oceanography explain some patterns of replenishment, the role of other growth-related processes in influencing settlement and recruitment is less clear. Examination of a 65-mo. time series of recruitment of a common coral reef fish, Stegastes partitus, to the reefs of the upper Florida Keys revealed that during peak recruitment months, settlement stage larvae arriving during dark lunar phases grew faster as larvae and were larger at settlement compared to those settling during the light lunar phases. However, the strength and direction of early trait-mediated selective mortality also varied by settlement lunar phase such that the early life history traits of 2-4 week old recruit survivors that settled across the lunar cycle converged to more similar values. Similarly, within peak settlement periods, early life history traits of settling larvae and selective mortality of recruits varied by the magnitude of the settlement event: larvae settling in larger events had longer PLDs and consequently were larger at settlement than those settling in smaller pulses. Traits also varied by recruitment habitat: recruits surviving in live coral habitat (vs rubble or areas with higher densities of adult conspecifics were those that were larger at settlement. Reef habitats, especially those with high densities of territorial conspecifics, are more challenging habitats for young fish to occupy and small settlers (due to lower larval growth and/or shorter PLDs to these habitats have a lower chance of survival than they do in rubble habitats. Settling reef fish are not all equal and the time and location of settlement influences the likelihood that individuals will survive to contribute to the population.

  17. Formulation and Validation of an Efficient Computational Model for a Dilute, Settling Suspension Undergoing Rotational Mixing

    Energy Technology Data Exchange (ETDEWEB)

    Sprague, Michael A.; Stickel, Jonathan J.; Sitaraman, Hariswaran; Crawford, Nathan C.; Fischer, Paul F.

    2017-04-11

    Designing processing equipment for the mixing of settling suspensions is a challenging problem. Achieving low-cost mixing is especially difficult for the application of slowly reacting suspended solids because the cost of impeller power consumption becomes quite high due to the long reaction times (batch mode) or due to large-volume reactors (continuous mode). Further, the usual scale-up metrics for mixing, e.g., constant tip speed and constant power per volume, do not apply well for mixing of suspensions. As an alternative, computational fluid dynamics (CFD) can be useful for analyzing mixing at multiple scales and determining appropriate mixer designs and operating parameters. We developed a mixture model to describe the hydrodynamics of a settling cellulose suspension. The suspension motion is represented as a single velocity field in a computationally efficient Eulerian framework. The solids are represented by a scalar volume-fraction field that undergoes transport due to particle diffusion, settling, fluid advection, and shear stress. A settling model and a viscosity model, both functions of volume fraction, were selected to fit experimental settling and viscosity data, respectively. Simulations were performed with the open-source Nek5000 CFD program, which is based on the high-order spectral-finite-element method. Simulations were performed for the cellulose suspension undergoing mixing in a laboratory-scale vane mixer. The settled-bed heights predicted by the simulations were in semi-quantitative agreement with experimental observations. Further, the simulation results were in quantitative agreement with experimentally obtained torque and mixing-rate data, including a characteristic torque bifurcation. In future work, we plan to couple this CFD model with a reaction-kinetics model for the enzymatic digestion of cellulose, allowing us to predict enzymatic digestion performance for various mixing intensities and novel reactor designs.

  18. Research advances and challenges in one-dimensional modeling of secondary settling tanks--a critical review.

    Science.gov (United States)

    Li, Ben; Stenstrom, M K

    2014-11-15

    Sedimentation is one of the most important processes that determine the performance of the activated sludge process (ASP), and secondary settling tanks (SSTs) have been frequently investigated with the mathematical models for design and operation optimization. Nevertheless their performance is often far from satisfactory. The starting point of this paper is a review of the development of settling theory, focusing on batch settling and the development of flux theory, since they played an important role in the early stage of SST investigation. The second part is an explicit review of the established 1-D SST models, including the relevant physical law, various settling behaviors (hindered, transient, and compression settling), the constitutive functions, and their advantages and disadvantages. The third part is a discussion of numerical techniques required to solve the governing equation, which is usually a partial differential equation. Finally, the most important modeling challenges, such as settleability description, settling behavior understanding, are presented.

  19. Colloidal Swarms Can Settle Faster than Isolated Particles: Enhanced Sedimentation near Phase Separation

    Science.gov (United States)

    Lattuada, Enrico; Buzzaccaro, Stefano; Piazza, Roberto

    2016-01-01

    By experimenting on model colloids where depletion forces can be carefully tuned and quantified, we show that attractive interactions consistently "promote" particle settling, so much that the sedimentation velocity of a moderately concentrated dispersion can even exceed its single-particle value. At larger particle volume fraction ϕ , however, hydrodynamic hindrance eventually takes over. Hence, v (ϕ ) actually displays a nonmonotonic trend that may threaten the stability of the settling front to thermal perturbations. Finally, by discussing a representative case, we show that these results are relevant to the investigation of protein association effects by ultracentrifugation.

  20. Settling distances of benthic invertebrates in a sediment mobilization simulation in semi-natural flumes

    Directory of Open Access Journals (Sweden)

    Maria Cristina Bruno

    2015-10-01

    Full Text Available Drift time and distance depend on the ability of the drifting invertebrates to alter their body posture or by swimming, and these behaviors may change according to the local hydraulic environment, resulting in different distances travelled before exiting the drift. Such drift and settlement mediated invertebrate movement determine dispersal processes and ultimately generates distribution patterns within streams. We conducted an experiment in an open-air, artificial flume system directly fed by an Alpine stream, where we disturbed the sediment in the flumes, inducing catastrophic drift in the benthic community, and then assessed the settlement distances of benthic invertebrates. For each flume, we collected drift samples by disturbing the substrate at 1.5 m intervals, at increasing distance from the downstream end, for a total of 7 disturbances and a maximum settling distance of 10 m in each flume, with five replicates (i.e., five flumes for each disturbance. The disturbances induced a massive catastrophic drift in Ephemeroptera, Plecoptera and Trichoptera, always higher than the behaviorally-occurring basedrift. The Settling Index calculated over the total drift collected at each distance increased with increasing distance, and after 10 m, 90% of the drifting animals had settled. Evenness and taxa richness progressively decrease with increasing settling distance. All drifting taxa were represented mainly by young instars. We used the drift collected at 1 m from the disturbance to standardize the remaining samples, based on the assumption that 1 m is not a distance long enough to allow animals to settle at that water velocity. We calculated the percentage of possible drifters which settled by computing a Settling Index for each taxon. The drifting taxa listed by decreasing Settling Index scores were Epeorus sp., Rhithrogena semicolorata, Isoperla spp., Sericostoma spp., Ecdyonurus spp., Nemoura spp., Leuctra spp., Baetis spp., Hydropsyche spp

  1. Laboratory evaluation of products to reduce settling of sweetpotato whitefly adults.

    Science.gov (United States)

    Schuster, D J; Thompson, S; Ortega, L D; Polston, J E

    2009-08-01

    The impact of trademarked and commercial products on settling of adults of the sweetpotato whitefly, Bemisia tabaci (Gennadius), was studied in the laboratory. A no-choice bioassay using leaf disks of tomato, Solanum esculentum L., was developed to evaluate the impact of concentration series of products on settling of B. tabaci adults. The concentration of each product that would reduce settling by 50% (SC50) was estimated for each product using standard probit analyses, and the values were compared with that of Ultra-Fine Oil, a paraffinic oil product that is known to reduce settling of whitefly adults. Twenty-two trademarked products and 42 other products were evaluated in the laboratory bioassay. Based upon comparisons of fiducial limits of the respective SC50 values, Dawn detergent and E-RASE jojoba oil were the only trademarked products that were as effective as Ultra-Fine Oil in reducing settling of B. tabaci adults. Of the nontrademarked products, 25 were similar to Ultra-Fine Oil, although cedar, geranium, ginger, Hamlin (citrus), patchouli, olive and wintergreen oils, as well as citronellal and limonene, had ratios of respective SC50 values with that of Ultra-Fine Oil of approximately 1.5 or less. Combinations of limonene and citronellal with either olive oil or Ultra-Fine Oil were 15 and 30 times, respectively, more effective than Ultra-Fine Oil alone. Candidate products and combinations of products were further evaluated on tomato seedlings in no-choice screenhouse trials for effects on oviposition and on transmission of Tomato yellow leaf curl virus (family Geminiviridae, genus Begomovirus, TYLCV) by B. tabaci. Ultra-Fine Oil and olive oil reduced oviposition and transmission of TYLCV in the screenhouse trials. Ginger oil and limonene reduced oviposition in at least one screenhouse trial but did reduce transmission of TYLCV. The laboratory bioassay provided a rapid and relatively easy method to compare products for reducing settling of B. tabaci adults

  2. Association between CYP1A1m1 gene polymorphism and primary open-angle glaucoma.

    Science.gov (United States)

    Costa, N B; Silva, C T X; Frare, A B; Silva, R E; Moura, K K V O

    2014-12-04

    The CYP1A1 gene is related to the generation of secondary metabolites that are capable of inducing DNA damage. The CYP1A1m1 polymorphism has been examined in many studies, and is located in a region near loci that have been linked to glaucoma, including the locus GLC1I. As a result, this polymorphism has been related to several diseases that are influenced by exposure to xenobiotic as well as primary open-angle glaucoma. We compared the prevalence of the CYP1A1m1 polymorphism in 152 Brazilian patients, 100 patients with primary open-angle glaucoma, and 52 normal controls using restriction fragment length polymorphism analysis. The frequency of the homozygous wild-type (w1/w1) CYP1A1 gene among patients with primary open-angle glaucoma (N = 100) was 16%, for genotype w1/m1, the frequency was 77%, and for m1/m1 it was 7%. Among the control group (N = 52), the frequency of the homozygous wild-type (w1/w1) CYP1A1 gene was 54%, the frequency of w1/m1 was 46%, and the frequency of m1/m1 was 0%. The presence of the CYP1A1m1 polymorphism may interfere with xenobiotic metabolism and exacerbate direct or indirect damage to the optic nerve. These CYP1A1m1 polymorphisms may be risk factors for primary open-angle glaucoma.

  3. Why Our Graduates Are Settling in Other States: And Why We Shouldn't Care

    Science.gov (United States)

    Trostel, Philip A.

    2009-01-01

    "Since so many graduates of our public colleges settle in other states, why should our state subsidize the workforce development of other states?" Or, "Why should we get more people into college when we won't have enough jobs for more college graduates here?" These widespread sentiments among people involved in public higher education indicate a…

  4. Heavy Metal and PAH Concentrations in Highway Runoff Deposits Fractionated on Settling Velocities

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben

    2009-01-01

    The correlation between settling velocity and associated pollutant concentrations is of major importance for best management practice in designing, redesigning, or evaluation of the efficiency of existing pond facilities for retaining unwanted pollutants. The prospect of this note is to state the...

  5. Novel instrumentation for online monitoring of stationary beds and their height for settling slurries

    CSIR Research Space (South Africa)

    Ilgner, Hartmut J

    2016-06-01

    Full Text Available Novel instrumentation has been developed to detect stationary bed conditions for settling slurries by using externally-mounted sensor heads with a heater and a temperature sensor. These heads are configured in such a way that suitable data...

  6. Turning PID Controller Tuning Into a Simple Consideration of Settling Time

    DEFF Research Database (Denmark)

    Jakobsen, Carl; Jantzen, Jan

    2016-01-01

    This article introduces an approach to PID tuning based solely on a physically meaningful performance specifica- tion: settling time. The approach leads to extremely simple tuning procedures which avoid potentially excessive excitation of the process. Provided that the closed loop system meets tw...

  7. Particle imaging velocimetry experiments and lattice-Boltzmann simulations on a single sphere settling under gravity

    NARCIS (Netherlands)

    Ten Cate, A.; Nieuwstad, C.H.; Derksen, J.J.; Van den Akker, H.E.A.

    2002-01-01

    A comparison is made between experiments and simulations on a single sphere settling in silicon oil in a box. Cross-correlation particle imaging velocimetry measurements were carried out at particle Reynolds numbers ranging from 1.5 to 31.9. The particle Stokes number varied from 0.2 to 4 and at bot

  8. Synthesis of modified polyacrylamide with high content of hydroxamate groups and settling performance of red mud

    Institute of Scientific and Technical Information of China (English)

    刘锦伟; 胡慧萍; 王梦; 陈湘攀; 陈启元; 丁治英

    2015-01-01

    Hydroxamated polyacrylamide (HPAM) was synthesized from polyacrylamide (PAM) with high relative molecular mass under the optimum reaction conditions (pH 12 and a molar ratio of hydroxylamine to amide groups of 1.5 at 50 °C for 12 h). The hydroxamate groups of HPAM were verified by Fourier transform infrared spectrum (FT-IR). 46% (molar fration) hydroxamate groups and 23% (molar fraction) carbonyl groups on HPAM were determined by conductometric titration combined with Kjeldahl’s microanalysis method. The settling performance achieved at different flocculant dosages was investigated with high goethite-containing red mud slurry of simulated Bayer process synthesized in laboratory. It turns out that the settling performance of high goethite-containing red mud was better with HPAM. The average settling rate of red mud in the first 5 min and the turbidity of supernatant after settling for 30 min are 2.36 m/h and 507 NTU, respectively, at a flocculant dosage of 120 g/t, which is similar to that achieved with Hx-600.

  9. The effect of the ammonium ion on activated-sludge settling properties

    DEFF Research Database (Denmark)

    Novak, John Thomas

    2001-01-01

    High levels of sodium in wastewater have been found to be detrimental to activated-sludge. settling and dewatering. Another potentially troublesome monovalent cation in activated-sludge systems is the ammonium ion. This study was conducted to determine if the ammonium ion could alter activated-sl...

  10. Thyroid spindle epithelial tumor with thymus-like differentiation (SETTLE): is cytopathological diagnosis possible?

    Science.gov (United States)

    Kloboves-Prevodnik, Veronika; Jazbec, Janez; Us-Krasovec, Marija; Lamovec, Janez

    2002-05-01

    Spindle epithelial tumor with thymus-like differentiation (SETTLE) is a rare tumor of the thyroid gland which occurs predominantly in children, adolescents, and young adults. It usually presents as a painless neck or thyroid mass and only exceptionally as a diffusely enlarged thyroid gland, without metastatic disease at diagnosis. We report on the case of 12-yr-old girl who had diffusely enlarged thyroid gland for about 1 yr and was initially treated for thyroiditis. Fine-needle aspiration biopsy (FNAB) was performed 8 mo after the first admission. Cytological examination of smears showed unusual morphological features. FNAB smears were cellular, with dissociated cells, naked oval nuclei, aggregates, and groups. Three main cell types were observed: spindle, epithelioid, and epithelial. These cells were uniform, cytologically bland, with few mitotic figures. The distinction between these cells was not always unequivocal. In the background of the smears abundant red extracellular material in the form of fine, dust-like granules and irregular patches were present. It was also observed in some aggregates and groups of tumor cells. Spindle and epithelioid cells were immunocytochemically diffusely pan-cytokeratin-positive. In the differential diagnosis, medullary thyroid carcinoma and SETTLE were suggested. The final histological diagnosis was SETTLE. In cases of SETTLE presented as a diffuse thyromegaly the correct diagnosis may be delayed because clinically and ultrasonographically thyroiditis is suspected. To avoid such a delay, FNAB should be used preoperatively. It can provide specific cytological diagnosis based on morphological features and certain immunocytochemical characteristics of the tumor.

  11. 45 CFR 681.42 - Can the administrative complaint be settled voluntarily?

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Can the administrative complaint be settled voluntarily? 681.42 Section 681.42 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROGRAM FRAUD CIVIL REMEDIES ACT REGULATIONS Decisions and Appeals § 681.42 Can the...

  12. Endotoxin levels in settled airborne dust in European schools: the HITEA school study.

    NARCIS (Netherlands)

    Jacobs, J.H.; Krop, E.J.M.; Borràs-Santos, A.; Zock, J.P.; Täubel, M.; Hyvärinen, A.; Pekkanen, J.; Doekes, G.; Heederik, D.J.J.

    2014-01-01

    Indoor exposure to microbial agents is known to influence respiratory health. Besides home exposure, exposure in schools can affect respiratory health. In this study, we measured endotoxin in settled dust in primary schools in three European countries from three different geographical regions with d

  13. Flow Scales of Influence on the Settling Velocities of Particles with Varying Characteristics

    Science.gov (United States)

    Jacobs, Corrine N.; Merchant, Wilmot; Jendrassak, Marek; Limpasuvan, Varavut; Gurka, Roi; Hackett, Erin E.

    2016-01-01

    The settling velocities of natural, synthetic, and industrial particles were measured in a grid turbulence facility using optical measurement techniques. Particle image velocimetry and 2D particle tracking were used to measure the instantaneous velocities of the flow and the particles’ trajectories simultaneously. We find that for particles examined in this study (Rep = 0.4–123), settling velocity is either enhanced or unchanged relative to stagnant flow for the range of investigated turbulence conditions. The smallest particles’ normalized settling velocities exhibited the most consistent trends when plotted versus the Kolmogorov-based Stokes numbers suggesting that the dissipative scales influence their dynamics. In contrast, the mid-sized particles were better characterized with a Stokes number based on the integral time scale. The largest particles were largely unaffected by the flow conditions. Using proper orthogonal decomposition (POD), the flow pattern scales are compared to particle trajectory curvature to complement results obtained through dimensional analysis using Stokes numbers. The smallest particles are found to have trajectories with curvatures of similar scale as the small flow scales (higher POD modes) whilst mid-sized particle trajectories had curvatures that were similar to the larger flow patterns (lower POD modes). The curvature trajectories of the largest particles did not correspond to any particular flow pattern scale suggesting that their trajectories were more random. These results provide experimental evidence of the “fast tracking” theory of settling velocity enhancement in turbulence and demonstrate that particles align themselves with flow scales in proportion to their size. PMID:27513958

  14. Influence of flocculation and settling properties of activated sludge in relation to secondary settler performance.

    Science.gov (United States)

    Wilén, B M; Onuki, M; Hermansson, M; Lumley, D; Mino, T

    2006-01-01

    Floc characteristics were studied at a full scale activated sludge treatment plant with a unique process solution incorporating pre-denitrification with post-nitrification in nitrifying trickling filters. Since greater nitrogen removal is achieved when more secondary settled wastewater is recirculated to the trickling filters, the secondary settlers are always operated close to their maximal capacity. The flocculation and settling properties are therefore crucial and have an effect on the overall plant performance. Since the plant is operated at a short sludge age, these properties change quickly, resulting in variable maximal secondary settler capacity. The dynamics in floc structure and microbial community composition were studied and correlated to the secondary settler performance. Fluorescence in situ hybridisation was used to investigate the microbial community structure and their spatial distribution. The floc structure could to some extent be related to the flocculation and settling properties of the sludge. Even small differences had an influence suggesting that colloidal properties also play a significant role in determining the floc properties. No correlation between microbial community composition and settling properties could be established with the group-specific probes investigated.

  15. Development and validation of a novel monitoring system for batch flocculant solids settling process

    DEFF Research Database (Denmark)

    Valverde Pérez, Borja; Zhang, Xueqian; Penkarski-Rodon, Elena

    2017-01-01

    Secondary sedimentation is the main hydraulic bottleneck of effective pollution control WWTP under wetweather flow conditions. Therefore, online monitoring tools are required for control and optimization of the settling process under dynamic conditions. In this work we propose a novel monitoring...

  16. 13 CFR 142.38 - Can the administrative complaint be settled voluntarily?

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Can the administrative complaint be settled voluntarily? 142.38 Section 142.38 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION PROGRAM FRAUD CIVIL REMEDIES ACT REGULATIONS Decisions and Appeals § 142.38 Can the...

  17. Relationship between settling time and pole-zero placements for three-stage CMOS opamp

    Science.gov (United States)

    Bhanu Singh Chandrawat, Uday; Mishra, D. K.

    2011-07-01

    In this article, the effect of pole-zero placements on settling time has been analysed for a three-stage CMOS operational amplifier (opamp) with nested Miller compensation (NMC) and reversed nested Miller compensation (RNMC) schemes. In this study, optimised balancing of speed and power is done for a three-stage CMOS opamp for a given load condition (on-chip opamp). Optimum values of circuit parameters have been derived for power efficient shifting of poles and zeros. The effect of placement of poles and zeros on dynamic settling error (DSE) is analysed by means of numerical simulation using MATLAB. This analysis will be useful to ascertain the relationship between pole-zero placements and settling time. The study of the effects of compensation elements on pole-zero placements has been done to assist the circuit designers to achieve better performance. Analysis of the effect of capacitive load on pole-zero placements and DSE has been done in this study. A technique has been developed to find out the upper and lower limits of compensation capacitor that allows fast settling with low power. The validity of the analytical work has been checked by simulation using Tanner tool in 0.35-µm CMOS technology. In the case of RNMC scheme, a power dissipation of 60.17 µw and a settling time of 340 ns are achieved; the results obtained are better than the earlier reported design technique. In the case of NMC, the simulation has been done to validate the analytical analysis.

  18. Trace metals, anions and polybromodiphenyl ethers in settled indoor dust and their association.

    Science.gov (United States)

    Kefeni, Kebede K; Okonkwo, Jonathan O

    2013-07-01

    Contaminants in settled indoor dust are potentially health hazardous to human. Thus, identification and quantification of toxic chemicals in settled indoor dust is of great concern. In this study, the levels of major anions ([Formula: see text]), trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, As and Pb) and polybromodiphenyl ethers (PBDEs) in settled office and home dust were determined and correlations between the contaminants investigated. Depending on the available materials in both microenvironments, the most possible sources were identified. The results showed that the settled office dusts (n = 6 pooled samples from 85 offices) were more contaminated than home dusts (n = 8 homes). For anions, [Formula: see text] and Cl(-) accounted for 87 and 97% of the total office and home dust contaminants, respectively. For trace metals, Fe, Cu, Zn and Mn, accounted for 98% of the contaminants in both office and home dust samples. Fe exhibited the highest percentage of 76.7 and 87.3% in office and home dust samples, respectively. For PBDEs, the mean concentrations detected in office and home dust ranged between 5.8-86.3 and 1.5-20.6 ng g(-1), respectively. The log-transformed correlation between the total concentrations of trace metals and major anions detected in offices and homes was positive for offices and negative for homes with a statistically significant values (r = 0.73, p < 0.01; r = -0.22, p < 0.01, respectively). The daily exposure rates determined for the most hazardous such as As, Cd, Pb and PBDEs congeners, relative to the individual concentrations reported in the literature in settled indoor dust, were found very lower. Therefore, maybe it is possible to expect less potential health risk. Investigation of formation of coordination compounds between trace metals and PBDEs congeners is possible; however, this requires further study.

  19. A model for thin layer formation by delayed particle settling at sharp density gradients

    Science.gov (United States)

    Prairie, Jennifer C.; White, Brian L.

    2017-02-01

    Thin layers - regions where plankton or particles accumulate vertically on scales of a few meters or less - are common in coastal waters, and have important implications for both trophic dynamics and carbon cycling. These features can form by a variety of biological and physical mechanisms, including localized growth, shear-thinning, and directed swimming. An additional mechanism may result in the formation of thin layers of marine aggregates, which have been shown to decrease their settling velocity when passing through sharp density gradients, a behavior termed delayed settling. Here, we apply a simple vertical advection-diffusion model to predict the properties of aggregate thin layers formed by this process. We assume a constant vertical flux of particles from the surface, which is parameterized by observations from laboratory experiments with marine aggregates. The formation, maintenance, and shape of the layers are described in relation to non-dimensional numbers that depend on environmental conditions and particle settling properties. In particular, model results demonstrate layer intensity and sharpness both increase with higher Péclet number (Pe), that is, under conditions with weaker mixing relative to layer formation. Similarly, more intense and sharper layers are found when the delayed settling behavior of aggregates is characterized by a lower velocity minimum. The model also predicts layers that are vertically asymmetric and highly "peaky" when compared with a Gaussian distribution, features often seen in thin layers in natural environments. Lastly, by comparing model predictions with observations of thin layers in the field, we are able to gain some insight into the applicability of delayed settling as a thin layer formation mechanism in different environmental conditions.

  20. SAR studies on carboxylic acid series M(1) selective positive allosteric modulators (PAMs).

    Science.gov (United States)

    Kuduk, Scott D; Beshore, Douglas C

    2014-01-01

    There is mounting evidence from preclinical and early proof-of-concept studies suggesting that selective modulation of the M1 muscarinic receptor is efficacious in cognitive models of Alzheimer's disease (AD). A number of nonselective M1 muscarinic agonists have previously shown positive effects on cognitive function in AD patients, but were limited due to cholinergic adverse events thought to be mediated by pan activation of the M2 to M5 sub-types. Thus, there is a need to identify selective activators of the M1 receptor to evaluate their potential in cognitive disorders. One strategy to confer selectivity for M1 is the identification of allosteric agonists or positive allosteric modulators, which would target an allosteric site on the M1 receptor rather than the highly conserved orthosteric acetylcholine binding site. BQCA has been identified as a highly selective carboxylic acid M1 PAM and this review focuses on an extensive lead optimization campaign undertaken on this compound.

  1. M1 Protein Allows Group A Streptococcal Survival in Phagocyte Extracellular Traps through Cathelicidin Inhibition

    OpenAIRE

    Lauth, Xavier; von Köckritz-Blickwede, Maren; McNamara, Case W; Myskowski, Sandra; Zinkernagel, Annelies S.; Beall, Bernard; Ghosh, Partho; Richard L Gallo; Nizet, Victor

    2009-01-01

    M1 protein contributes to Group A Streptococcus (GAS) systemic virulence by interfering with phagocytosis and through proinflammatory activities when released from the cell surface. Here we identify a novel role of M1 protein in the stimulation of neutrophil and mast cell extracellular trap formation, yet also subsequent survival of the pathogen within these DNA-based innate defense structures. Targeted mutagenesis and heterologous expression studies demonstrate M1 protein promotes resistance...

  2. Non-viral FoxM1 gene delivery to hepatocytes enhances liver repopulation.

    Science.gov (United States)

    Xiang, D; Liu, C-C; Wang, M-J; Li, J-X; Chen, F; Yao, H; Yu, B; Lu, L; Borjigin, U; Chen, Y-X; Zhong, L; Wangensteen, K J; He, Z-Y; Wang, X; Hu, Y-P

    2014-05-22

    Hepatocyte transplantation as a substitute strategy of orthotopic liver transplantation is being studied for treating end-stage liver diseases. Several technical hurdles must be overcome in order to achieve the therapeutic liver repopulation, such as the problem of insufficient expansion of the transplanted hepatocytes in recipient livers. In this study, we analyzed the application of FoxM1, a cell-cycle regulator, to enhance the proliferation capacity of hepatocytes. The non-viral sleeping beauty (SB) transposon vector carrying FoxM1 gene was constructed for delivering FoxM1 into the hepatocytes. The proliferation capacities of hepatocytes with FoxM1 expression were examined both in vivo and in vitro. Results indicated that the hepatocytes with FoxM1 expression had a higher proliferation rate than wild-type (WT) hepatocytes in vitro. In comparison with WT hepatocytes, the hepatocytes with FoxM1 expression had an enhanced level of liver repopulation in the recipient livers at both sub-acute injury (fumaryl acetoacetate hydrolase (Fah)(-/-) mice model) and acute injury (2/3 partial hepatectomy mice model). Importantly, there was no increased risk of tumorigenicity with FoxM1 expression in recipients even after serial transplantation. In conclusion, expression of FoxM1 in hepatocytes enhanced the capacity of liver repopulation without inducing tumorigenesis. FoxM1 gene delivered by non-viral SB vector into hepatocytes may be a viable approach to promote therapeutic repopulation after hepatocyte transplantation.

  3. Monocyte Differentiation towards Protumor Activity Does Not Correlate with M1 or M2 Phenotypes

    Directory of Open Access Journals (Sweden)

    G. Karina Chimal-Ramírez

    2016-01-01

    Full Text Available Macrophages facilitate breast cancer progression. Macrophages were initially classified as M1 or M2 based on their distinct metabolic programs and then expanded to include antitumoral (M1 and protumoral (M2 activities. However, it is still uncertain what markers define the pro- and antitumoral phenotypes and what conditions lead to their formation. In this study, monocytic cell lines and primary monocytes were subjected to commonly reported protocols of M1/M2 polarization and conditions known to engage monocytes into protumoral functions. The results showed that only IDO enzyme and CD86 M1 markers were upregulated correlating with M1 polarization. TNF-α, CCR7, IL-10, arginase I, CD36, and CD163 were expressed indistinguishably from M1 or M2 polarization. Similarly, protumoral engaging resulted in upregulation of both M1 and M2 markers, with conditioned media from the most aggressive breast cancer cell line promoting the greatest changes. In spite of the mixed phenotype, M1-polarized macrophages exhibited the highest expression/secretion of inflammatory mediators, many of which have previously been associated with breast cancer aggressiveness. These data argue that although the existence of protumoral macrophages is unquestionable, their associated phenotypes and the precise conditions driving their formation are still unclear, and those conditions may need both M1 and M2 stimuli.

  4. Monocyte Differentiation towards Protumor Activity Does Not Correlate with M1 or M2 Phenotypes

    Science.gov (United States)

    Chimal-Ramírez, G. Karina; Espinoza-Sánchez, Nancy Adriana; Chávez-Sánchez, Luis; Arriaga-Pizano, Lourdes

    2016-01-01

    Macrophages facilitate breast cancer progression. Macrophages were initially classified as M1 or M2 based on their distinct metabolic programs and then expanded to include antitumoral (M1) and protumoral (M2) activities. However, it is still uncertain what markers define the pro- and antitumoral phenotypes and what conditions lead to their formation. In this study, monocytic cell lines and primary monocytes were subjected to commonly reported protocols of M1/M2 polarization and conditions known to engage monocytes into protumoral functions. The results showed that only IDO enzyme and CD86 M1 markers were upregulated correlating with M1 polarization. TNF-α, CCR7, IL-10, arginase I, CD36, and CD163 were expressed indistinguishably from M1 or M2 polarization. Similarly, protumoral engaging resulted in upregulation of both M1 and M2 markers, with conditioned media from the most aggressive breast cancer cell line promoting the greatest changes. In spite of the mixed phenotype, M1-polarized macrophages exhibited the highest expression/secretion of inflammatory mediators, many of which have previously been associated with breast cancer aggressiveness. These data argue that although the existence of protumoral macrophages is unquestionable, their associated phenotypes and the precise conditions driving their formation are still unclear, and those conditions may need both M1 and M2 stimuli. PMID:27376091

  5. Larvae of the Commercial Tropical Oyster Crassostrea belcheri (Sowerby) are induced to settle by Pheromones from the Adults

    DEFF Research Database (Denmark)

    Bussarawit, Somchai; Cedhagen, Tomas

    2012-01-01

    other species within the same genus or from a different genus. Settling frequency was increased by the presence of living oysters together with soaked spatfall collectors in commercial aquaculture. The fact that larvae are induced to settle by pheromones released from the adults is an important...

  6. 21 CFR 1404.635 - May the Office of National Drug Control Policy settle a debarment or suspension action?

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false May the Office of National Drug Control Policy settle a debarment or suspension action? 1404.635 Section 1404.635 Food and Drugs OFFICE OF NATIONAL DRUG... Suspension and Debarment Actions § 1404.635 May the Office of National Drug Control Policy settle a...

  7. Velocity oscillations and stop-go cycles: The trajectory of an object settling in a cornstarch suspension

    NARCIS (Netherlands)

    von Kann, S.; Snoeijer, Jacobus Hendrikus; van der Meer, Roger M.

    2013-01-01

    We present results for objects settling in a cornstarch suspension. Two surprising phenomena can be found in concentrated suspensions. First, the settling object does not attain a terminal velocity but exhibits oscillations around a terminal velocity when traveling through the bulk of the liquid. Se

  8. Significance of settling model structures and parameter subsets in modelling WWTPs under wet-weather flow and filamentous bulking conditions

    DEFF Research Database (Denmark)

    Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen;

    2014-01-01

    Current research focuses on predicting and mitigating the impacts of high hydraulic loadings on centralized wastewater treatment plants (WWTPs) under wet-weather conditions. The maximum permissible inflow to WWTPs depends not only on the settleability of activated sludge in secondary settling tanks...... (SSTs) but also on the hydraulic behaviour of SSTs. The present study investigates the impacts of ideal and non-ideal flow (dry and wet weather) and settling (good settling and bulking) boundary conditions on the sensitivity of WWTP model outputs to uncertainties intrinsic to the one-dimensional (1-D...... of settling parameters to the total variance of the key WWTP process outputs significantly depends on the influent flow and settling conditions. The magnitude of the impact is found to vary, depending on which type of 1-D SST model is used. Therefore, we identify and recommend potential parameter subsets...

  9. Experimental Conditions: SE37_S19_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available opes SE37_S19 PSEUDO: Unlabeled and labeled Medicago samples for flavonoid annotation using ShiftedIonsFinde...03_M1) and for a blank sample (S16_M1 to S16_M3) are used. Import file name is unlabeling SE37_DS5 Flavonoid like peak search by ShiftedIonsFinder ...

  10. Radioiodinated ganglioside G/sub M1/: A potential tracer for neurological studies

    Energy Technology Data Exchange (ETDEWEB)

    Zalutsky, M.R.; Gallagher, P.; Magistretti, P.L.; Ghidoni, R.

    1985-05-01

    Ganglioside G/sub M1/ is a glycosphingolipid which appears to be involved in the regeneration of damaged neuronal tissue. In addition, it is being investigated clinically in the treatment of various neuropathies. If labeled with the appropriate isotope, G/sub M1/ might be useful as a probe of these processes, particularly if it accumulates preferentially in cerebral infarcts. The G/sub M1/ -tyr derivative was labeled with I-125 in 75% yield using the Iodogen method and at micellar concentration was isolated using gel chromatography. Binding of I-125 (G/sub M1/ -tyr) to rat neuronal membranes was measured at concentrations of 5,50, and 500 nM. The amount bound (8,26, and 158 pmol/gm membrane) was similar to that reported for H-3(G/sub M1/). The biodistribution of I-125(G/sub M1/ -tyr) in mice at both micellar and monomeric concentrations was also similar to that of H-3(G/sub M1/). However, at monomeric concentrations, thyroid uptake of I-125 was about 10 times higher than at micellar concentrations, suggesting differential dehalogenation of the two forms. Initial studies in the gerbil stroke model suggest that the uptake of I-125(G/sub M1/ -tyr) in damaged brain is twice that in normal tissue.

  11. CONDITIONAL INVOLVEMENT OF MUSCARINIC M(1) RECEPTORS IN VAGALLY MEDIATED CONTRACTION OF GUINEA-PIG BRONCHI

    NARCIS (Netherlands)

    TENBERGE, REJ; ROFFEL, AF; ZAAGSMA, J

    The involvement of ganglionic muscarinic M(1) receptors in vagally induced bronchoconstriction in guinea-pig airways is controversial. Therefore, we studied the effects of the M(1)-selective muscarinic receptor antagonist pirenzepine on vagus nerve (VNS, preganglionic) and electrical field

  12. A note on predicting recessions in the euro area using real M1

    OpenAIRE

    Jens Boysen-Hogrefe

    2012-01-01

    Real M1 is a renowned leading indicator used to forecast real economic activity. This note provides evidence that real M1 is also a suitable recession indicator that gave a clear and early signal for the Great Recession as long as changes in money demand are controlled for.

  13. Analytical Method (M): SE37_S18_M1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE37_S18_M1 This is a pseudo metadata prepared for integrated analyses of multiple ...datasets. The raw data obtained from LC-Orbitarp MS analyses for Medicago samples and a blank sample (S17_M1

  14. 12 CFR Appendix M1 to Part 226 - Generic Repayment Estimates

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Generic Repayment Estimates M1 Appendix M1 to Part 226 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE... rounded down to the nearest whole year if the estimate contains a fractional year less than 0.5,...

  15. Experimental Conditions: SE19_S2_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE19_S2_M1_D1 SE19 Grobal triacylglycerol analysis in mouse liver and white adipose... tissue (WAT) by high resolution LC/ESI-QTOF MS/MS SE19_S2 Mouse white adipose tissue (WAT) SE19_S2_M1 20 ug

  16. FoxM1 is required for execution of the mitotic programme and chromosome stability

    NARCIS (Netherlands)

    Laoukili, J.; Kooistra, M.R.H.; Brás, A.; Kauw, J.; Kerkhoven, R.M.; Morrison, A.; Clevers, H.C.; Medema, R.H.

    2005-01-01

    Transcriptional induction of cell-cycle regulatory proteins ensures proper timing of subsequent cell-cycle events. Here we show that the Forkhead transcription factor FoxM1 regulates expression of many G2-specific genes and is essential for chromosome stability. Loss of FoxM1 leads to pleiotropic ce

  17. FoxM1 is required for execution of the mitotic programme and chromosome stability.

    NARCIS (Netherlands)

    Laoukili, J.; Kooistra, M.R.H.; Bras, A.; Kauw, J.; Kerkhoven, R.M.; Morrison, A.; Clevers, J.C.; Medema, R.H.

    2005-01-01

    Transcriptional induction of cell-cycle regulatory proteins ensures proper timing of subsequent cell-cycle events. Here we show that the Forkhead transcription factor FoxM1 regulates expression of many G2-specific genes and is essential for chromosome stability. Loss of FoxM1 leads to pleiotropic ce

  18. Nanometre-accurate form measurement machine for E-ELT M1 segments

    NARCIS (Netherlands)

    Bos, A.; Henselmans, R.; Rosielle, P.C.J.N.; Steinbuch, M.

    2015-01-01

    To enable important scientific discoveries, ESO has defined a new ground-based telescope: the European Extremely Large Telescope (E-ELT). The baseline design features a telescope with a 39-m-class primary mirror (M1), making it the largest and most powerful telescope in the world. The M1 consists of

  19. Regional distribution of M1, M2 and non-M1, non-M2 subtypes of muscarinic binding sites in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Ehlert, F.J.; Tran, L.P. (Univ. of California, Irvine (USA))

    1990-12-01

    The distribution of subtypes of the muscarinic receptor in homogenates of the rat brain was investigated by measuring the competitive inhibition of the binding (3H)N-methylscopolamine by pirenzepine and AF-DX 116 (11((2-((diethylamino)methyl)-1-piperidinyl)acetyl)-5, 11-dihydro-6H-pyrido(2,3-b)(1,4)benzodiazepine-6-one). In most brain regions, the competitive binding curves for AF-DX 116 and pirenzepine were consistent with a two-site model. The dissociation constant of pirenzepine for its high-affinity site (M1 receptor) was approximately 10(-8) M, whereas the dissociation constant of AF-DX 116 for its high affinity site (M2 receptor) was approximately 10(-7) M. In many regions, particularly those in the forebrain, the sum of the densities of the M1 and M2 binding sites was substantially less than 100% of the total sites, indicating the existence of a third population of sites lacking high affinity for both pirenzepine and AF-DX 116. We have designated these latter sites as non-M1, non-M2 muscarinic receptors. In general, the densities of the M1 and non-M1, non-M2 binding sites were highest in cerebral cortex, corpus striatum and hippocampus, intermediate in thalamus and hypothalamus, and lowest in midbrain, medulla-pons and cerebellum, whereas the M2 binding site had a relatively low, uniform density throughout the brain. The binding capacity of (3H)N-methylquinuclidinyl benzilate was estimated to be 20 to 30% lower than that of (3H)quinuclidinyl benzilate in various regions of the forebrain, but not in more caudal regions of the brain where the two radioligands had approximately the same binding capacities.

  20. The luminosity function of cluster galaxies relations among M$_{1}$, M* and the morphological type

    CERN Document Server

    Trevese, D; Appodia, B

    1996-01-01

    A study of the luminosity function of 36 Abell clusters of galaxies has been carried out using photographic plates obtained with the Palomar 1.2 m Schmidt telescope. The relation between the magnitude M_1 of the brightest cluster member and the Schechter function parameter M* has been analyzed. A positive correlation between M* and M_1 is found. However clusters appear segregated in the M_1-M* plane according to their Rood & Sastry class in such a way that on average M_1 becomes brighter while M* becomes fainter going from late to early Rood & Sastry and also Bautz & Morgan classes. Also a partial correlation analysis involving the magnitude M_10 of the 10th brightest galaxy, shows a negative intrinsic correlation between M_1 and M*. These results agree with the cannibalism model for the formation of brightest cluster members, and provide new constraints for theories of cluster formation and evolution.

  1. Effects of Lactobacillus kefiranofaciens M1 isolated from kefir grains on germ-free mice.

    Directory of Open Access Journals (Sweden)

    Yen-Po Chen

    Full Text Available Lactobacillus kefiranofaciens M1 is a novel probiotic strain that was isolated from kefir grains. Previously, we have demonstrated the immunoregulatory, anti-allergic, anti-asthmatic and anti-colitis abilities of L. kefiranofaciens M1 in a number of in-vitro and in-vivo experiments. However, whether the effects of L. kefiranofaciens M1 are elicited directly on the host or act by regulating the host's microbiota remains unknown. A number of studies have used germ-free or gnotobiotic animals to investigate the relationship between probiotics and colitis; therefore the aim of this study was to investigate the effects of L. kefiranofaciens M1 on germ-free mice. Such an approach should help in determining the direct effects of L. kefiranofaciens M1 on the host itself. Four-week-old female germ-free mice were inoculated intragastrically with 2×10(8 CFU/mouse L. kefiranofaciens M1 once or at 2-day intervals for 14 days. Bacterial colonization, the Th1/Th2 cytokine profile of the mice's splenocytes and the anti-colitis effect of L. kefiranofaciens M1 were investigated. The strongest response in terms of splenic Th1 cytokine IFN-γ and IL-12 production upon TLR activation was detected in the continuous treatment group when comparing to the single inoculation group and the germ-free control. In addition, continuous inoculation with L. kefiranofaciens M1 was found to ameliorate the symptoms of DSS-induced colitis in germ-free mice. However, L. kefiranofaciens M1 failed to colonize the host. Thus it would seem that L. kefiranofaciens M1 is likely to act directly on the host and not be involved in microbiota regulation.

  2. Velocity fluctuations and population distribution in clusters of settling particles at low Reynolds number

    CERN Document Server

    Boschan, A; Annichini, M; Gauthier, G

    2016-01-01

    A study on the spatial organization and velocity fluctuations of non Brownian spherical particles settling at low Reynolds number in a vertical Hele-Shaw cell is reported. The particle volume fraction ranged from 0.005 to 0.05, while the distance between cell plates ranged from 5 to 15 times the particle radius. Particle tracking revealed that particles were not uniformly distributed in space but assembled in transient settling clusters. The population distribution of these clusters followed an exponential law. The measured velocity fluctuations are in agreement with that predicted theoretically for spherical clusters, from the balance between the apparent weight and the drag force. This result suggests that particle clustering, more than a spatial distribution of particles derived from random and independent events, is at the origin of the velocity fluctuations.

  3. Numerical modelling of melting and settling of an encapsulated PCM using variable viscosity

    Science.gov (United States)

    Kasibhatla, Raghavendra Rohith; König-Haagen, Andreas; Rösler, Fabian; Brüggemann, Dieter

    2016-10-01

    Thermal energy storage units using macro-encapsulated PCM in industrial and residential applications are contemporary due to better efficiency during charging and discharging. This article focuses on numerical modelling of the melting process in a macro-encapsulated PCM. Accounting the non-linear enthalpy-temperature relation and ramping down the velocity in solid phase is therefore fundamental. In the present article the variable viscosity method is implemented to ramp down the solid velocity and allow settling of the solid phase. This complete numerical model of melting and settling of PCM in a capsule is implemented in OpenFOAM. The numerical results for different solid viscosities are validated with experiments and show good agreement. The influence of the solid viscosity value and the pressure-velocity convergence is studied. It is observed that the pressure-velocity convergence only plays a greater role in the case where the computation of the exact solid velocity is required.

  4. Scales of influence on the settling velocities of synthetic, industrial and natural particles in grid turbulence

    CERN Document Server

    Jacobs, Corrine; Jendrassak, Marek; Limpasuvan, Varavut; Gurka, Roi; Hackett, Erin E

    2015-01-01

    The settling velocities of natural, synthetic, and industrial particles were measured in a grid turbulence facility using optical measurement techniques. Particle Image Velocimetry and 2D Particle Tracking were used to measure the instantaneous velocities of the flow and the particles' trajectories simultaneously. We find that for particles examined in this study (Rep = 0.4 - 123), settling velocity is either enhanced or unchanged relative to stagnant flow for the range of investigated turbulence conditions. The smallest particles scaled best with a Kolmogorov-based Stokes number indicating the dissipative scales influence their dynamics. In contrast, the mid-sized particles scaled better with a Stokes number based on the integral time scale. The largest particles were largely unaffected by the flow conditions. Using Proper Orthogonal Decomposition (POD), the flow pattern scales are compared to particle trajectory curvature to complement results obtained through dimensional analysis using Stokes numbers. The ...

  5. Feedforward Compensation by Specified Step Settling Considering Constraint on Control Input

    Science.gov (United States)

    Hirose, Noriaki; Iwasaki, Makoto; Hirai, Hiromu

    This paper presents a novel design approach for feedforward compensation by employing specified step settling to provide fast and precise positioning control of mechatronic systems. In the conventional approach, the saturation of control input essentially deteriorates the control performance in terms of response time and residual vibration suppression. However, in the proposed method of feedforward compensation, command shaping is performed within the deadbeat control framework, wherein a constraint on the control input can be imposed by using the LMI technique to ensure the desired control performance. Therefore, by using the proposed approach, a 2-degrees-of-freedom positioning controller can achieve the required settling performance without causing residual vibration under the constraint. The effectiveness of the proposed approach has been verified by carrying out numerical simulations and experiments on a prototype.

  6. Characteristics and settling behaviour of particles from blast furnace flue gas washing.

    Science.gov (United States)

    Kiventerä, Jenni; Leiviskä, Tiina; Keski-Ruismäki, Kirsi; Tanskanen, Juha

    2016-05-01

    A lot of particles from iron-making are removed with blast furnace off-gas and routed to the gas cleaning system. As water is used for cleaning the gas, the produced wash water contains a large amount of particles such as valuable Fe and C. However, the presence of zinc prevents recycling. In addition, the high amount of calcium results in uncontrolled scaling. Therefore, the properties of the wash water from scrubber and sludge, from the Finnish metal industry (SSAB Raahe), were evaluated in this study. Size fractionation of wash water revealed that Fe, Zn, Al, Mn, V, Cr and Cd appeared mainly in the larger fractions (>1.2 μm) and Na, Mg, Si, Ni, K, Cu and As appeared mainly in the smaller fractions (<1.2 μm) or in dissolved form. Calcium was found both in the larger fractions and dissolved (∼60 mg/L). Most of the particles in wash water were included in the 1.2-10 μm particle size and were settled effectively. However, a clear benefit was observed when using a chemical to enhance particle settling. In comparison to 2.5 h of settling without chemical, the turbidity was further decreased by about 94%, iron 85% and zinc 50%. Coagulation-flocculation experiments indicated that both low and high molecular weight cationic polymers could provide excellent purification results in terms of turbidity. Calcium should be removed by other methods. The particles in sludge were mostly in the 2-4 μm or 10-20 μm fractions. Further sludge settling resulted in high solids removal.

  7. Biomass density and filament length synergistically affect activated sludge settling: systematic quantification and modeling.

    Science.gov (United States)

    Jassby, D; Xiao, Y; Schuler, A J

    2014-01-01

    Settling of the biomass produced during biological treatment of wastewater is a critical and often problematic process. Filamentous bacteria content is the best-known factor affecting biomass settleability in activated sludge wastewater treatment systems, and varying biomass density has recently been shown to play an important role as well. The objective of this study was to systematically determine how filament content and biomass density combine to affect microbial biomass settling, with a focus on density variations over the range found in full-scale systems. A laboratory-scale bioreactor system was operated to produce biomass with a range of filamentous bacterium contents. Biomass density was systematically varied in samples from this system by addition of synthetic microspheres to allow separation of filament content and density effects on settleability. Fluorescent in-situ hybridization indicated that the culture was dominated by Sphaerotilus natans, a common contributor to poor settling in full-scale systems. A simple, image-based metric of filament content (filament length per floc area) was linearly correlated with the more commonly used filament length per dry biomass measurement. A non-linear, semi-empirical model of settleability as a function of filament content and density was developed and evaluated, providing a better understanding of how these two parameters combine to affect settleability. Filament content (length per dry biomass weight) was nearly linearly related to sludge volume index (SVI) values, with a slightly decreasing differential, and biomass density exhibited an asymptotic relationship with SVI. The filament content associated with bulking was shown to be a function of biomass density. The marginal effect of filament content on settleability increased with decreasing biomass density (low density biomass was more sensitive to changes in filament content than was high density biomass), indicating a synergistic relationship between these

  8. Effect of surface structure of kaolinite on aggregation, settling rate, and bed density.

    Science.gov (United States)

    Du, Jianhua; Morris, Gayle; Pushkarova, Rada A; Smart, Roger St C

    2010-08-17

    The flocculation and solid/liquid separation of four well-characterized kaolinites (2 well, 2 poorly crystallized) have been studied for comparison of surface structure (SEM), aggregate structure during flocculation (cryo-SEM), settling rate, and bed density (with raking). It is shown that major differences in these properties are largely due to crystallinity and consequent surface structure of the extensive (larger dimension "basal") face. Well-crystallized kaolinites, with higher Hinckley indices and lower aspect ratios, have relatively smooth, flat basal surfaces and thicker edge planes promoting both effective initial bridging flocculation (largely edge-edge) and structural rearrangement to face-face during the raking process. This results in faster settling rates and more compact bed structures. Poorly crystallized kaolinites, with low Hinckley indices and high aspect ratios, exhibit ragged, stepped structures of the extensive face with a high proportion of nanosized islands forming cascade-like steps (i.e., multiple edges) contributing up to 30% of the specific surface area and providing flocculant adsorption sites (hydroxyl groups) across this extensive face. This leads to bridging flocculation taking place on both edge and extensive ("basal") planes, producing low-density edge-face structures during flocculation which leads to slow settling rates and poor bed densities. In particular, the complex surface morphology of the poorly crystallized kaolinites resists the transformation of edge-face structures to dense face-face structures under shear force introduced by raking. This results in low sediment density for poorly crystallized kaolinites. The studies suggest that the main influence on settling rates and bed densities of kaolinites in mineral tailings is likely to be related to the crystallinity and surface morphology of the kaolinite. They also suggest that interpretation of kaolinite behavior based on models of a flat (001) basal plane and edge sites

  9. Accelerated Settling of Marine Particulate Matter by ’Marine Snow’ Aggregates.

    Science.gov (United States)

    1986-03-01

    this material arrives at both depths within the same sampling interval indicates that these gelatinous zooplankton remains settle at more than 175 m day...of the remains of plankton , sinking in some stages of disintegration..." For the purpose of this paper, flocs, flakes, fecal matter, aggregates, large...Enlargement of (a). The excellent preservation of the coccoliths indicates rapid vertical transport. Scale bar is 2pm. c) Fragment of planktonic

  10. Columnar structure formation of a dilute suspension of settling spherical particles in a quiescent fluid

    CERN Document Server

    Huisman, Sander G; Bourgoin, Mickaël; Chouippe, Agathe; Doychev, Todor; Huck, Peter; Morales, Carla E Bello; Uhlmann, Markus; Volk, Romain

    2016-01-01

    The settling of heavy spherical particles in a column of quiescent fluid is investigated. The performed experiments cover a range of Galileo numbers ($110 \\leq \\text{Ga} \\leq 310$) for a fixed density ratio of $\\Gamma = \\rho_p/\\rho_f = 2.5$. In this regime the particles are known (M. Jenny, J. Du\\v{s}ek and G. Bouchet, Journal of Fluid Mechanics 508, 201 (2004).) to show a variety of motions. It is known that the wake undergoes several transitions for increasing $\\text{Ga}$ resulting in particle motions that are successively: vertical, oblique, oblique oscillating, and finally chaotic. Not only does this change the trajectory of single, isolated, settling particles, but it also changes the dynamics of a swarm of particles as collective effects become important even for dilute suspensions, with volume fraction up to $\\Phi_V = \\mathcal{O}\\left(10^{-3}\\right)$, which are investigated in this work. Multi-camera recordings of settling particles are recorded and tracked over time in 3 dimensions. A variety of analy...

  11. Improving Settling Characteristics of Pure Oxygen Activated Sludge by Stripping of Carbon Dioxide.

    Science.gov (United States)

    Kundral, Somshekhar; Mudragada, Ratnaji; Coro, Ernesto; Moncholi, Manny; Mora, Nelson; Laha, Shonali; Tansel, Berrin

    2015-06-01

    Increased microbial activity at high ambient temperatures can be problematic for secondary clarifiers and gravity concentrators due to carbon dioxide (CO2) production. Production of CO2 in gravity concentrators leads to septic conditions and poor solids separation. The CO2 production can also be corrosive for the concrete surfaces. Effectiveness of CO2 stripping to improve solids settling was investigated using the sludge volume index (SVI) as the indicator parameter. Carbon dioxide was stripped by aeration from the sludge samples. Results from the study show that aeration also increased the pH values in the mixed liquor while removing CO2 and improving sludge settling. After 10 minutes of aeration at a rate of 0.37 m3 air/m3 water/min, 90% CO2 stripping was achieved. Based on the 30 min settling tests, the SVI increased by 26±1% after CO2 stripping while the pH increased by 0.8±0.1 pH units.

  12. A consistent modelling methodology for secondary settling tanks in wastewater treatment.

    Science.gov (United States)

    Bürger, Raimund; Diehl, Stefan; Nopens, Ingmar

    2011-03-01

    The aim of this contribution is partly to build consensus on a consistent modelling methodology (CMM) of complex real processes in wastewater treatment by combining classical concepts with results from applied mathematics, and partly to apply it to the clarification-thickening process in the secondary settling tank. In the CMM, the real process should be approximated by a mathematical model (process model; ordinary or partial differential equation (ODE or PDE)), which in turn is approximated by a simulation model (numerical method) implemented on a computer. These steps have often not been carried out in a correct way. The secondary settling tank was chosen as a case since this is one of the most complex processes in a wastewater treatment plant and simulation models developed decades ago have no guarantee of satisfying fundamental mathematical and physical properties. Nevertheless, such methods are still used in commercial tools to date. This particularly becomes of interest as the state-of-the-art practice is moving towards plant-wide modelling. Then all submodels interact and errors propagate through the model and severely hamper any calibration effort and, hence, the predictive purpose of the model. The CMM is described by applying it first to a simple conversion process in the biological reactor yielding an ODE solver, and then to the solid-liquid separation in the secondary settling tank, yielding a PDE solver. Time has come to incorporate established mathematical techniques into environmental engineering, and wastewater treatment modelling in particular, and to use proven reliable and consistent simulation models.

  13. A consistent modelling methodology for secondary settling tanks: a reliable numerical method.

    Science.gov (United States)

    Bürger, Raimund; Diehl, Stefan; Farås, Sebastian; Nopens, Ingmar; Torfs, Elena

    2013-01-01

    The consistent modelling methodology for secondary settling tanks (SSTs) leads to a partial differential equation (PDE) of nonlinear convection-diffusion type as a one-dimensional model for the solids concentration as a function of depth and time. This PDE includes a flux that depends discontinuously on spatial position modelling hindered settling and bulk flows, a singular source term describing the feed mechanism, a degenerating term accounting for sediment compressibility, and a dispersion term for turbulence. In addition, the solution itself is discontinuous. A consistent, reliable and robust numerical method that properly handles these difficulties is presented. Many constitutive relations for hindered settling, compression and dispersion can be used within the model, allowing the user to switch on and off effects of interest depending on the modelling goal as well as investigate the suitability of certain constitutive expressions. Simulations show the effect of the dispersion term on effluent suspended solids and total sludge mass in the SST. The focus is on correct implementation whereas calibration and validation are not pursued.

  14. Coagulation settling characteristics and eliminating pollution analysis of fine-grind natural zeolite in static and turbulent flow.

    Science.gov (United States)

    Zhu, Ruirui; Zhu, Jianzhong; Chen, Liang

    2014-05-01

    The phenomenon of coagulation settling in liquid suspensions has a variety of applications, including mineral processing, treatment of industrial effluents, and municipal sewage sludge purification. This study was to investigate the coagulation settling characteristics of fine-grind natural zeolite and evaluate the removal efficiency of contaminants simultaneously in static and turbulent flow. A series of column experiments were conducted to pattern the characteristics of spatial and temporal variation of coagulation settling and removal contaminants in static and turbulent flow. The results indicated that the suspended solid concentration presented an apparent exponential decay with coagulation settling time in static flow (R (2)  > 0.99), coagulation settling rate of the fine zeolite-suspended solid in static flow was between 0.005 and 0.05 cm/s obtained from the repeat depth suction method. The relation between average C/C 0 of pollutants and suspended solid concentration was exponential before the settlement for 24 h and that was the line after the settlement for 24 h. Several various models were presented to highlight the coagulation settling characteristics of fine-grind natural zeolite in static and turbulent flow. Compared to hydrostatic settling experiments, zeolite-suspended solid presented better removal efficiency of pollutants and greater removal rate of pollutants in turbulent flow.

  15. Exploration of FoxM1 and downstream related target molecule expression in cervical cancer tissue

    Institute of Scientific and Technical Information of China (English)

    Yi-Chong Yuan; QiongYang

    2016-01-01

    Objective:To study the expression of FoxM1 and downstream related target molecules in cervical cancer tissue.Methods:Cervical cancer tissue and normal cervical tissue were collected to detect the expression of FoxM1, proliferation-related genes (CDK6 and CDK8) and angiogenesis-related genes (VEGFA, VEGFB and VEGFC); Hela cells were cultured and transfected with FoxM1 siRNA, and then expression of CDK6, CDK8, VEGFA, VEGFB and VEGFC were detected.Results:mRNA contents of FoxM1, CDK6, CDK8, VEGFA, VEGFB and VEGFC in cervical cancer tissue were significantly higher than those in normal cervical tissue; mRNA content of FoxM1 was positively correlated with mRNA contents of CDK6, CDK8, VEGFA, VEGFB and VEGFC; mRNA contents of CDK6, CDK8, VEGFA, VEGFB and VEGFC of FoxM1-siRNA group were significantly lower than those of negative control-siRNA group.Conclusion:FoxM1 expression abnormally increases in cervical cancer tissue, and its downstream target genes include CDK6, CDK8, VEGFA, VEGFB and VEGFC.

  16. Emergence and oscillation of cosmic space by joining M1-branes

    CERN Document Server

    Sepehri, Alireza; Capozziello, Salvatore; Ali, Ahmed Farag; Pradhan, Anirudh

    2016-01-01

    Recently, it has been proposed by Padmanabhan that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region leads to the expansion of the universe. Now, a natural question arises, how this model could explain the oscillation of universe between contraction and expansion branches? We try to address this issue in the framework of BIonic system. In this model, $M0$-branes join to each other and give rise to a pair of $M1$-anti-$M1$-branes. The fields which live on these branes play the roles of massive gravitons that cause the emergence of a wormhole between them and formation of a BIon system. This wormhole dissolves into M1-branes and causes a divergence between the number of degrees of freedom on the boundary surface of $M1$ and the bulk leading to an expansion of $M1$-branes. When $M1$-branes become close to each other, the square energy of their system becomes negative and some tachyonic states emerge. To removes these states, $M1$...

  17. Enzyme-linked immunosorbent assay for determination of aflatoxin M1 based on magnetic nanoparticles

    Science.gov (United States)

    Atanasova, M. K.; Ivanova, N. V.; Godjevargova, T. I.

    2017-02-01

    A sensitive enzyme immunoassay with magnetic nanoparticles (Method A) for the quantitative determination of aflatoxin M1 in milk was developed. This immunoassay was based on the immobilization of monoclonal antibody (mAb) on the modified magnetic nanoparticles (MNPs-NH2). It was observed that for each mg of the MNPs, 25 µg of antibody was immobilized. Both aflatoxin M1 in the sample and aflatoxin M1-BSA-peroxidase conjugate competed for the immobilized antibody. The proposed Method A was compared with other method (B). The Method B was based on the immobilization of aflatoxin M1-BSA conjugate on the MNPs-NH2, which competed with the aflatoxin M1 in the sample for binding to the added mAb. The binding of mAb to the aflatoxin M1-BSA-MNPs-NH2 was detected using a target secondary IgG-peroxidase antibody. The analytical characteristics of the two methods were compared. Real milk samples were investigated for present of aflatoxin M1. Two methods were based on the use of MNPs as a solid support for covalently immunoreagents immobilization. A comfortable separation of bound and free fraction of the tracer can be performed only through a simple collection of the MNPs by a permanent magnet. The application of MNPs helps to eliminate non-specific binding and to retain higher activity of bound biomolecules. The development of a MNPs-based ELISA for determination of aflatoxin M1 has a great potential to supersede the traditional ELISA for aflatoxin M1 diagnosis.

  18. Bounds on Subspace Codes Based on Subspaces of Type (m,1 in Singular Linear Space

    Directory of Open Access Journals (Sweden)

    You Gao

    2014-01-01

    Full Text Available The Sphere-packing bound, Singleton bound, Wang-Xing-Safavi-Naini bound, Johnson bound, and Gilbert-Varshamov bound on the subspace codes n+l,M,d,(m,1q based on subspaces of type (m,1 in singular linear space Fq(n+l over finite fields Fq are presented. Then, we prove that codes based on subspaces of type (m,1 in singular linear space attain the Wang-Xing-Safavi-Naini bound if and only if they are certain Steiner structures in Fq(n+l.

  19. TANK 21 AND TANK 24 BLEND AND FEED STUDY: BLENDING TIMES, SETTLING TIMES, AND TRANSFERS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.; Leishear, R.; Poirier, M.

    2012-05-31

    The Salt Disposition Integration (SDI) portfolio of projects provides the infrastructure within existing Liquid Waste facilities to support the startup and long term operation of the Salt Waste Processing Facility (SWPF). Within SDI, the Blend and Feed Project will equip existing waste tanks in the Tank Farms to serve as Blend Tanks where salt solutions of up to 1.2 million gallons will be blended in 1.3 million gallon tanks and qualified for use as feedstock for SWPF. In particular, Tanks 21 and 24 are planned to be used for blending and transferring to the SDI feed tank. These tanks were evaluated here to determine blending times, to determine a range of settling times for disturbed sludge, and to determine that the SWPF Waste Acceptance Criteria that less than 1200 mg/liter of solids will be entrained in salt solutions during transfers from the Tank 21 and Tank 24 will be met. Overall conclusions for Tank 21 and Tank 24 operations include: (1) Experimental correction factors were applied to CFD (computational fluid dynamics) models to establish blending times between approximately two and five hours. As shown in Phase 2 research, blending times may be as much as ten times greater, or more, if lighter fluids are added to heavier fluids (i.e., water added to salt solution). As the densities of two salt solutions converge this effect may be minimized, but additional confirmatory research was not performed. (2) At the current sludge levels and the presently planned operating heights of the transfer pumps, solids entrainment will be less than 1200 mg/liter, assuming a conservative, slow settling sludge simulant. (3) Based on theoretical calculations, particles in the density range of 2.5 to 5.0 g/mL must be greater than 2-4 {micro}m in diameter to ensure they settle adequately in 30-60 days to meet the SWPF feed criterion (<1200 mg/l). (4) Experimental tests with sludge batch 6 simulant and field turbidity data from a recent Tank 21 mixing evolution suggest the solid

  20. RHEOLOGY OF SETTLED SOLIDS IN THE SMALL COLUMN ION EXCHANGE PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, C.; Prior, M.; Koopman, D.; Edwards, T.

    2011-06-20

    The Small Column Ion Exchange (SCIX) process is being developed to remove cesium, strontium, and actinides from Savannah River Site (SRS) Liquid Waste using an existing waste tank as process housing. This method includes the addition of monosodium titanate (MST) to a waste tank containing salt solution and entrained sludge solids, followed by tank mixing and filtration. The filtrate is then processed through in-tank ion exchange columns containing crystalline silicotitanate (CST) media. While the process is operating, it is known that solid particles begin to settle in the tank and temperatures may reach beyond 45 C. Previous testing has shown that sludge-MST slurries that sit for extended periods at elevated temperatures can develop large shear strengths, making them difficult to resuspend and remove from the tank. The authors conducted rheological testing of mixtures containing various concentrations of sludge simulant, MST, and CST (three preparations) that were aged at different times (i.e., 0 to 13 weeks) and isothermally maintained to 30, 45, or 60 C. Two types of grinding methodologies were employed to prepare CST for this testing, herein called Savannah River National Laboratory (SRNL) and Vitreous State Laboratory (VSL) ground materials. Unground CST particles were also tested. A small number of samples were irradiated prior to 4 week settling and 60 C temperature treatment, with exposures ranging from 0 to 100 MRad. Additional tests are also being conducted that will allow the solid particles to settle at 45 C for 6, 12, and 24 months. The objectives of this task are to determine the impact of feed composition, settling time, and temperature on the shear strength, yield stress, and consistency of the slurries and to determine the impact of radiation on slurry rheology. The testing will determine the relative impact of these parameters rather than predict the shear strength, yield stress, and consistency as a function of feed and operating conditions. This

  1. Numerical Modelling of Volcanic Ash Settling in Water Using Adaptive Unstructured Meshes

    Science.gov (United States)

    Jacobs, C. T.; Collins, G. S.; Piggott, M. D.; Kramer, S. C.; Wilson, C. R.

    2011-12-01

    At the bottom of the world's oceans lies layer after layer of ash deposited from past volcanic eruptions. Correct interpretation of these layers can provide important constraints on the duration and frequency of volcanism, but requires a full understanding of the complex multi-phase settling and deposition process. Analogue experiments of tephra settling through a tank of water demonstrate that small ash particles can either settle individually, or collectively as a gravitationally unstable ash-laden plume. These plumes are generated when the concentration of particles exceeds a certain threshold such that the density of the tephra-water mixture is sufficiently large relative to the underlying particle-free water for a gravitational Rayleigh-Taylor instability to develop. These ash-laden plumes are observed to descend as a vertical density current at a velocity much greater than that of single particles, which has important implications for the emplacement of tephra deposits on the seabed. To extend the results of laboratory experiments to large scales and explore the conditions under which vertical density currents may form and persist, we have developed a multi-phase extension to Fluidity, a combined finite element / control volume CFD code that uses adaptive unstructured meshes. As a model validation, we present two- and three-dimensional simulations of tephra plume formation in a water tank that replicate laboratory experiments (Carey, 1997, doi:10.1130/0091-7613(1997)0252.3.CO;2). An inflow boundary condition at the top of the domain allows particles to flux in at a constant rate of 0.472 gm-2s-1, forming a near-surface layer of tephra particles, which initially settle individually at the predicted Stokes velocity of 1.7 mms-1. As more tephra enters the water and the particle concentration increases, the layer eventually becomes unstable and plumes begin to form, descending with velocities more than ten times greater than those of individual particles. The

  2. Locations of All Shotpoints, USGS Cruise M1-98-GM (GOM98SHTALLG.SHP)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — All shotpoint locations from multichannel seismics survey, USGS cruise M1-98-GM. During June 1998 and April 1999, the U.S. Geological Survey (USGS) conducted two...

  3. Aflatoxin M1 levels in raw milk, pasteurized milk and infant formula

    National Research Council Canada - National Science Library

    Omar, Sharaf Shareef

    2016-01-01

    The incidence of contamination of aflatoxin M1 (AFM1) in milk samples collected from the Jordanian market was investigated by using the competitive enzyme linked immunosorbent assay (ELISA) technique...

  4. Experimental Conditions: SE24_S1_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available rometry with 13C‑Labeling for Chemical Assignment of Sulfur-Containing Metabolites ...SE24_S1_M1_D1 SE24 Combination of Liquid Chromatography-Fourier Transform Ion Cyclotron Resonance-Mass Spect

  5. Towards Revised Step IV MICE Optics in the Absence of M1 SSD

    Energy Technology Data Exchange (ETDEWEB)

    Bayes, R. [Univ. of Glasgow, Scotland (United Kingdom); Berg, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blackmore, V. [Imperial College, London (United Kingdom); Hunt, C. [Imperial College, London (United Kingdom); Liu, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Pasternak, J. [Imperial College, London (United Kingdom); Rogers, C. T. [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL)

    2015-10-01

    During magnet commissioning in September 2015, the leads on coil M1 of the downstream spectrometer solenoid failed. The coil will not be operational for MICE Step IV. Revised optics settings for the Step IV data taking are reviewed.

  6. Coiled-Coil Irregularities and Instabilities in Group A Streptococcus M1 Are Required for Virulence

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, Case; Zinkernagel, Annelies S.; Macheboeuf, Pauline; Cunningham, Madeleine W.; Nizet, Victor; Ghosh, Partho (UO-HSC); (UCSD)

    2008-07-21

    Antigenically variable M proteins are major virulence factors and immunogens of the human pathogen group A Streptococcus (GAS). Here, we report the -3 angstrom resolution structure of a GAS M1 fragment containing the regions responsible for eliciting type-specific, protective immunity and for binding fibrinogen, which promotes M1 proinflammatory and antiphagocytic functions. The structure revealed substantial irregularities and instabilities throughout the coiled coil of the M1 fragment. Similar structural irregularities occur in myosin and tropomyosin, explaining the patterns of cross-reactivity seen in autoimmune sequelae of GAS infection. Sequence idealization of a large segment of the M1 coiled coil enhanced stability but diminished fibrinogen binding, proinflammatory effects, and antibody cross-reactivity, whereas it left protective immunogenicity undiminished. Idealized M proteins appear to have promise as vaccine immunogens.

  7. Presence of Aflatoxin M1 in Raw Milk for Human Consumption in Palestinian

    Directory of Open Access Journals (Sweden)

    Ibrahim Mahmoud AL ZUHEIR

    2012-09-01

    Full Text Available The absences or insufficient food control program result in the occurrence of mycotoxin in milk and milk products, which poses a serious risk for humans and can be a public health concern. This study was conducted to highlight the occurrence of aflatoxin M1 in Palestine raw milk collected at farms from Tulkarm, Nablus and Jenin. Aflatoxin M1 was determined by direct competitive ELISA technique. 85 % (34 of 40 of the total examined raw milk samples tested were positive. The aflatoxin M1 contamination levels were between 3 - 80 ppt with a mean of 29.57 ppt. There was a high incidence rate with 92 % (11 of 12 and the highest means of contaminated with aflatoxin M1 in the samples tested in Tulkarm city (P ≤ 0.05. 20 % of the analyzed samples (8 of 40 exceeded the maximum permissible limit (50 ppt in European Codex, with a range of 2 - 80 ppt.

  8. FoxM1 mediated resistance to gefitinib in non-small-cell lung cancer cells

    Institute of Scientific and Technical Information of China (English)

    Nuo XU; Xin ZHANG; Xun WANG; Hai-yan GE; Xiao-ying WANG; David GARFIELD; Ping YANG; Yuan-lin SONG; Chun-xue BAI

    2012-01-01

    Gefitinib is effective in only approximately 20% of patients with non-small-cell lung cancer (NSCLC),and the underlying mechanism remains unclear.FoxM1 is upregulated in NSCLC and associated with a poor prognosis in NSCLC patients.In this study,we examined the possible role of FoxM1 in gefitinib resistance and the related mechanisms.Methods:Gefitinib resistant human lung adenocarcinoma cell line SPC-A-1 and gefitinib-sensitive human lung mucoepidermoid carcinoma cell line NCI-H292 were used.mRNA and protein expression of FoxM1 and other factors were tested with quantitative RT PCR and Western blot analysis.RNA interference was performed to suppress FoxM1 expression in SPC-A-1 cells,and lentiviral infection was used to overexpress FoxM1 in H292 cells.MTT assay and flow cytometry were used to examine the proliferation and apoptosis of the cells.Results:Treatment of SPC-A-1 cells with gefitinib (1 and 10 μmol/L) upregulated the expression of FoxM1 in time- and concentrationdependent manners,while gefrtinib (1 μmol/L) downregulated in H292 cells.In SPC-A-1 cells treated with gefitinib (1 μmol/L),the expression of several downstream targets of FoxM1,including survivin,cyclin B1,SKP2,PLK1,Aurora B kinase and CDC25B,were significantly upregulated.Overexpression of FoxM1 increased the resistance in H292 cells,while attenuated FoxM1 expression restored the sensitivity to gefitinib in SPC-A-1 cells by inhibiting proliferation and inducing apoptosis.Conclusion:The results suggest that FoxM1 plays an important role in the resistance of NSCLC cells to gefitinib in vitro.FoxM1 could be used as a therapeutic target to overcome the resistance to gefitinib.

  9. Basins of Attraction for Generative Justice

    Science.gov (United States)

    Eglash, Ron; Garvey, Colin

    It has long been known that dynamic systems typically tend towards some state - an "attractor" - into which they finally settle. The introduction of chaos theory has modified our understanding of these attractors: we no longer think of the final "resting state" as necessarily being at rest. In this essay we consider the attractors of social ecologies: the networks of people, technologies and natural resources that makeup our built environments. Following the work of "communitarians" we posit that basins of attraction could be created for social ecologies that foster both environmental sustainability and social justice. We refer to this confluence as "generative justice"; a phrase which references both the "bottom-up", self-generating source of its adaptive meta stability, as well as its grounding in the ethics of egalitarian political theory.

  10. q-differential operator representation of the quantum superalgebra Uq(sl(M+1|N+1))

    CERN Document Server

    Kimura, K

    1996-01-01

    A representation of the quantum superalgebra Uq(sl(M+1|N+1)) is constructed based on the q-differential operators acting on the coherent states parameterized by coordinates. These coordinates correspond to the local ones of the flag manifold. This realization provides us with a guide to construct the free field realization for the quantum affine superalgebra Uq^(sl(M+1|N+1)) at arbitrary level.

  11. Aflatoxin M1 Contamination in Milk and Milk Products in Iran: A Review

    Directory of Open Access Journals (Sweden)

    R. Kazemi Darsanaki

    2013-11-01

    Full Text Available Mycotoxins are secondary metabolites of molds and have adverse effects on humans, animals, and crops. Those can cause illnesses and economic losses. Aflatoxin M1 (AFM1 is one of the mycotoxins produced from the hydroxylated metabolite of aflatoxin B1 (AFB1. It can be found in milk or milk products obtained from livestock that have ingested contaminated feed. In this paper, recent studies were reviewed in aflatoxin M1 contamination in milk and milk products in Iran.

  12. Aflatoxin M1 Contamination in Milk and Milk Products in Iran: A Review

    Directory of Open Access Journals (Sweden)

    R. Kazemi Darsanaki

    2014-05-01

    Full Text Available Mycotoxins are secondary metabolites of molds and have adverse effects on humans, animals, and crops. Those can cause illnesses and economic losses. Aflatoxin M1 (AFM1 is one of the mycotoxins produced from the hydroxylated metabolite of aflatoxin B1 (AFB1. It can be found in milk or milk products obtained from livestock that have ingested contaminated feed. In this paper, recent studies were reviewed in aflatoxin M1 contamination in milk and milk products in Iran.

  13. The Evaluation of Aflatoxin M1 Level in Collected Raw Milk for Pasteurized Dairy

    Directory of Open Access Journals (Sweden)

    Ehsan Sadeghi

    2013-03-01

    Full Text Available Background: Aflatoxins are fungal toxins that have carcinogenic, cellular mutations and malformation effects. Aflatoxin M1 resists pasteurization, autoclave and the other methods that make foodstuff healthy. This study aims to determine the contents of aflatoxin M1 in raw milk of milk factories in Kermanshah province.Materials and Methods: This research is carried out through the descriptive-cross sectional method. Among the raw milk received by four pasteurized milk factories in Kermanshah, coded by (A, B, C, D labels, six samples, totally 320 samples (80 samples from each factory, were taken within four seasons. The concentration of aflatoxin M1 was examined by Enzyme-Linked Immunosorbent Assay (ELISA. The mean difference was analyzed statistically through t-test using SPSS software. Results: The content of aflatoxin was higher than Codex standard (0.5 µg/l in 295 samples. The total mean was 1.21, which exceeds two times the Codex standard. The highest and lowest contents of aflatoxin M1 were observed in “Factory D” in spring and in “Factory A” in autumn, respectively. There was a significant difference between contamination of aflatoxin M1 and different seasons (p< 0.05.Conclusion: High content of aflatoxin M1 in raw milk is worrying. Measuring the content of aflatoxin M1 is essential to reduce the toxin entering the daily food of animals and the other related factors. The considerable difference of aflatoxin M1 content between Factory D and Factory A can be attributed to the amount of the local milk and the industrial milk received by the factories.

  14. Emergence and oscillation of cosmic space by joining M1-branes

    Energy Technology Data Exchange (ETDEWEB)

    Sepehri, Alireza [Shahid Bahonar University, Faculty of Physics, Kerman (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), Maragha (Iran, Islamic Republic of); Rahaman, Farook [Jadavpur University, Department of Mathematics, Kolkata, West Bengal (India); Capozziello, Salvatore [Universita di Napoli Federico II, Dipartimento di Fisica ' ' E. Pancini' ' , Naples (Italy); Gran Sasso Science Institute (INFN), L' Aquila (Italy); Tomsk State Pedagogical University, Tomsk (Russian Federation); INFN Sezione di Napoli, Naples (Italy); Ali, Ahmed Farag [Benha University, Department of Physics, Faculty of Science, Benha (Egypt); Pradhan, Anirudh [G L A University, Department of Mathematics, Institute of Applied Sciences and Humanities, Mathura, Uttar Pradesh (India)

    2016-05-15

    Recently, it has been proposed by Padmanabhan that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region leads to the expansion of the universe. Now, a natural question arises; how could this model explain the oscillation of the universe between contraction and expansion branches? We try to address this issue in the framework of a BIonic system. In this model, M0-branes join to each other and give rise to a pair of M1-anti-M1-branes. The fields which live on these branes play the roles of massive gravitons that cause the emergence of a wormhole between them and formation of a BIon system. This wormhole dissolves into M1-branes and causes a divergence between the number of degrees of freedom on the boundary surface of M1 and the bulk leading to an expansion of M1-branes. When M1-branes become close to each other, the square energy of their system becomes negative and some tachyonic states emerge. To remove these states, M1-branes become compact, the sign of compacted gravity changes, causing anti-gravity to arise: in this case, branes get away from each other. By articulating M1-BIons, an M3-brane and an anti-M3-brane are created and connected by three wormholes forming an M3-BIon. This new system behaves like the initial system and by closing branes to each other, they become compact and, by getting away from each other, they open. Our universe is located on one of these M3-branes and, by compactifying the M3-brane, it contracts and, by opening it, it expands. (orig.)

  15. Emergence and oscillation of cosmic space by joining M1-branes

    Science.gov (United States)

    Sepehri, Alireza; Rahaman, Farook; Capozziello, Salvatore; Ali, Ahmed Farag; Pradhan, Anirudh

    2016-05-01

    Recently, it has been proposed by Padmanabhan that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region leads to the expansion of the universe. Now, a natural question arises; how could this model explain the oscillation of the universe between contraction and expansion branches? We try to address this issue in the framework of a BIonic system. In this model, M0-branes join to each other and give rise to a pair of M1-anti- M1-branes. The fields which live on these branes play the roles of massive gravitons that cause the emergence of a wormhole between them and formation of a BIon system. This wormhole dissolves into M1-branes and causes a divergence between the number of degrees of freedom on the boundary surface of M1 and the bulk leading to an expansion of M1-branes. When M1-branes become close to each other, the square energy of their system becomes negative and some tachyonic states emerge. To remove these states, M1-branes become compact, the sign of compacted gravity changes, causing anti-gravity to arise: in this case, branes get away from each other. By articulating M1-BIons, an M3-brane and an anti- M3-brane are created and connected by three wormholes forming an M3-BIon. This new system behaves like the initial system and by closing branes to each other, they become compact and, by getting away from each other, they open. Our universe is located on one of these M3-branes and, by compactifying the M3-brane, it contracts and, by opening it, it expands.

  16. Enhanced M1/M2 macrophage ratio promotes orthodontic root resorption.

    Science.gov (United States)

    He, D; Kou, X; Luo, Q; Yang, R; Liu, D; Wang, X; Song, Y; Cao, H; Zeng, M; Gan, Y; Zhou, Y

    2015-01-01

    Mechanical force-induced orthodontic root resorption is a major clinical challenge in orthodontic treatment. Macrophages play an important role in orthodontic root resorption, but the underlying mechanism remains unclear. In this study, we examined the mechanism by which the ratio of M1 to M2 macrophage polarization affects root resorption during orthodontic tooth movement. Root resorption occurred when nickel-titanium coil springs were applied on the upper first molars of rats for 3 to 14 d. Positively stained odontoclasts or osteoclasts with tartrate-resistant acid phosphatase were found in resorption areas. Meanwhile, M1-like macrophages positive for CD68 and inducible nitric oxide synthase (iNOS) persistently accumulated on the compression side of periodontal tissues. In addition, the expressions of the M1 activator interferon-γ and the M1-associated pro-inflammatory cytokine tumor necrosis factor (TNF)-α were upregulated on the compression side of periodontal tissues. When the coil springs were removed at the 14th day after orthodontic force application, root resorption was partially rescued. The number of CD68(+)CD163(+) M2-like macrophages gradually increased on the compression side of periodontal tissues. The levels of M2 activator interleukin (IL)-4 and the M2-associated anti-inflammatory cytokine IL-10 also increased. Systemic injection of the TNF-α inhibitor etanercept or IL-4 attenuated the severity of root resorption and decreased the ratio of M1 to M2 macrophages. These data imply that the balance between M1 and M2 macrophages affects orthodontic root resorption. Root resorption was aggravated by an enhanced M1/M2 ratio but was partially rescued by a reduced M1/M2 ratio.

  17. Optical illusion alters M1 excitability after mirror therapy: a TMS study.

    Science.gov (United States)

    Läppchen, C H; Ringer, T; Blessin, J; Seidel, G; Grieshammer, S; Lange, R; Hamzei, F

    2012-11-01

    The contralesional primary motor cortex (M1) has been suggested to be involved in the motor recovery after mirror therapy, but whether the ipsilesional M1 is influenced by the contralesional M1 via transcallosal interhemispheric inhibition (IHI) is still unclear. The present study investigated the change of IHI as well as the intracortical inhibition and intracortical facilitation of both M1 induced by training in a mirror with the use of transcranial magnetic stimulation (TMS). In this 2 × 2 factorial design (time × group), healthy subjects exercised standardized motor skills with their right hand on four consecutive days. Either a mirror (mirror group) or a board (control group) was positioned between their hands. Before and after training TMS was applied along with training tests of both hands. Tests were the same motor skills exercised daily by both groups. Tests of the untrained left hand improved significantly more in the mirror group than in the control group after training (P = 0.02) and showed a close correlation with an increase of intracortical inhibition of M1(left). IHI did not show any difference between investigation time points and groups. The present study confirms the previous suggestion of the involvement of the "contralesional" left-side (ipsilateral to the hand behind the mirror) M1 after mirror therapy, which is not mediated by IHI. Even with the same motor skill training (both groups performed same motor skills) but with different visual information, different networks are involved in training-induced plasticity.

  18. Differential Roles of M1 and M2 Microglia in Neurodegenerative Diseases.

    Science.gov (United States)

    Tang, Yu; Le, Weidong

    2016-03-01

    One of the most striking hallmarks shared by various neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease (AD), and amyotrophic lateral sclerosis, is microglia-mediated neuroinflammation. Increasing evidence indicates that microglial activation in the central nervous system is heterogeneous, which can be categorized into two opposite types: M1 phenotype and M2 phenotype. Depending on the phenotypes activated, microglia can produce either cytotoxic or neuroprotective effects. In this review, we focus on the potential role of M1 and M2 microglia and the dynamic changes of M1/M2 phenotypes that are critically associated with the neurodegenerative diseases. Generally, M1 microglia predominate at the injury site at the end stage of disease, when the immunoresolution and repair process of M2 microglia are dampened. This phenotype transformation is very complicated in AD due to the phagocytosis of regionally distributed β-amyloid (Aβ) plaque and tangles that are released into the extracellular space. The endogenous stimuli including aggregated α-synuclein, mutated superoxide dismutase, Aβ, and tau oligomers exist in the milieu that may persistently activate M1 pro-inflammatory responses and finally lead to irreversible neuron loss. The changes of microglial phenotypes depend on the disease stages and severity; mastering the stage-specific switching of M1/M2 phenotypes within appropriate time windows may provide better therapeutic benefit.

  19. A-1 Petroleum in Washington settles with EPA to resolve spill prevention planning violations, protect local waters

    Science.gov (United States)

    (Seattle - Sept. 30, 2015) A-1 Petroleum and Propane, Inc., located in Ellensburg, Washington, has agreed to settle emergency planning violations with the U.S Environmental Protection Agency. A-1 Petroleum is the largest petroleum distributor in Kittitas C

  20. On-line determination of sludge settling velocity for flux-based real-time control of secondary clarifiers.

    Science.gov (United States)

    Lynggaard-Jensen, A; Lading, L

    2006-01-01

    The state diagram for operation of secondary clarifiers is used to design a control algorithm for the return sludge pumping and determination of the actual hydraulic capacity of the biological step of a wastewater treatment plant. On-line input for the control algorithm is derived from a sludge volume sensor and a suspended solids sensor in the form of software sensors giving values for the sludge settling characteristics - settling velocity, sludge volume index, initial settling velocity and the exponent in the Vesilind equation - allowing the control to accommodate the ever changing settling characteristics and thereby keep the suspended solids flux in the clarifiers in balance for both dry weather flows and during rain events. The control algorithm has been implemented, tested and set into normal operation on a full scale wastewater treatment plant.

  1. Liquid phase sintering, I: Computer study of skeletal settling and solid phase extrication in a normal gravity environment

    Directory of Open Access Journals (Sweden)

    Nikolić Z.S.

    2008-01-01

    Full Text Available In this paper we will investigate gravity induced skeletal settling during liquid phase sintering. In this approach skeletal settling will be combined with extrication of some solidphase domains. The main goal will be the need to relate dissolution, diffusion and precipitation phenomena to essential geometric and topological changes of the tungstennickel porous microstructure influenced by differential skeletal settling due to large density difference between tungsten domains and the matrix. This study will be based on domain topology (no shape restriction and control-volume methodology. The microstructural evolution will be simulated by computation of displacement of the center of mass (combined gravity induced settling and random motion and mass transport due to dissolution and precipitation at the interfaces between solid-phase and liquid matrix.

  2. The Plasmodium falciparum malaria M1 alanyl aminopeptidase (PfA-M1: insights of catalytic mechanism and function from MD simulations.

    Directory of Open Access Journals (Sweden)

    Peter M Jones

    Full Text Available Malaria caused by several species of Plasmodium is major parasitic disease of humans, causing 1-3 million deaths worldwide annually. The widespread resistance of the human parasite to current drug therapies is of major concern making the identification of new drug targets urgent. While the parasite grows and multiplies inside the host erythrocyte it degrades the host cell hemoglobin and utilizes the released amino acids to synthesize its own proteins. The P. falciparum malarial M1 alanyl-aminopeptidase (PfA-M1 is an enzyme involved in the terminal stages of hemoglobin digestion and the generation of an amino acid pool within the parasite. The enzyme has been validated as a potential drug target since inhibitors of the enzyme block parasite growth in vitro and in vivo. In order to gain further understanding of this enzyme, molecular dynamics simulations using data from a recent crystal structure of PfA-M1 were performed. The results elucidate the pentahedral coordination of the catalytic Zn in these metallo-proteases and provide new insights into the roles of this cation and important active site residues in ligand binding and in the hydrolysis of the peptide bond. Based on the data, we propose a two-step catalytic mechanism, in which the conformation of the active site is altered between the Michaelis complex and the transition state. In addition, the simulations identify global changes in the protein in which conformational transitions in the catalytic domain are transmitted at the opening of the N-terminal 8 Å-long channel and at the opening of the 30 Å-long C-terminal internal chamber that facilitates entry of peptides to the active site and exit of released amino acids. The possible implications of these global changes with regard to enzyme function are discussed.

  3. Influence of sludge properties and hydraulic loading on the performance of secondary settling tanks--full-scale operational results.

    Science.gov (United States)

    Vestner, R J; Günthert, F Wolfgang

    2004-01-01

    Full-scale investigations at a WWTP with a two-stage secondary settling tank process revealed relationships between significant operating parameters and performance in terms of effluent suspended solids concentration. Besides common parameters (e.g. surface overflow rate and sludge volume loading rate) feed SS concentration and flocculation time must be considered. Concentration of the return activated sludge may help to estimate the performance of existing secondary settling tanks.

  4. M1 contributes to the intrinsic but not the extrinsic components of motor-skills.

    Science.gov (United States)

    Romei, Vincenzo; Thut, Gregor; Ramos-Estebanez, Ciro; Pascual-Leone, Alvaro

    2009-10-01

    Procedural skills consist of several components that can be simultaneously acquired. During a motor-learning task we can distinguish between how a "movement" is performed (intrinsic component) and the spatial-related (extrinsic) component of this movement. The intrinsic movement component is thought to be supported by motor loops, including primary motor cortex (M1) as assessed with neuroimaging studies. Here we want to test further whether M1 makes a critical contribution to the movement rather than spatial-related component of skill-learning. To this purpose, we used repetitive Transcranial Magnetic Stimulation (rTMS) and the serial reaction time (SRT) task. Twenty right-handed participants performed the SRT-task starting with their left or right hand. After this learning session, participants switched to the untrained hand by performing original (spatial-related) and mirror-ordered (movement-based) sequences. rTMS was applied to M1 ipsi- or contralateral to the transfer-hand and both sequences were retested. Results revealed rTMS-interference with motor-skill transfer of mirror-ordered but not original sequences, showing that M1 is critically involved in the retrieval/transformation of the intrinsic but not the extrinsic movement coordinates. rTMS-interference in the mirror-condition consisted of both (i) disruption and (ii) release of motor-skill transfer depending on the stimulated hemisphere and on transfer-hand. The pattern of results suggests (i) contralateral (right) M1 involvement in retrieval/transformation of motor information during left-hand reproduction of previously acquired right-hand motor-skills; and (ii) modulatory interactions of inhibitory nature from the dominant (left) to the non-dominant (right) M1 in the same transfer-condition. These results provide further evidence that M1 is essential to intrinsic movement-based skill-learning and novel insight on models of motor-learning and hemispheric specialization, suggesting the involvement of

  5. Neoglycolipid analogues of ganglioside G sub M1 as functional receptors of cholera toxin

    Energy Technology Data Exchange (ETDEWEB)

    Pacuszka, T.; Bradley, R.M.; Fishman, P.H. (National Inst. of Health, Bethesda, MD (United States))

    1991-03-12

    The authors synthesized several lipid analogues of ganglioside G{sub M1} by attaching its oligosaccharide moiety (G{sub M1}OS) to aminophospholipids, aliphatic amines, and cholesteryl hemisuccinate. They incubated G{sub M1}-deficient rat glioma C6 cells with each of the derivatives as well as native G{sub M1} and assayed the cells for their ability to bind and respond to cholera toxin. On the basis of the observed increase in binding of {sup 125}I-labeled cholera toxin, it was apparent that the cells took up and initially incorporated most of the derivatives into the plasma membrane. In the case of the aliphatic amine derivatives, the ability to generate new toxin binding sites was dependent on chain length; whereas the C{sub 10} derivative was ineffective, C{sub 12} and higher analogues were effective. Increased binding was dependent on both the concentration of the neoglycolipid in the medium and the time of exposure. Cells pretreated with the various derivatives accumulated cyclic AMP in response to cholera toxin, but there were differences in their effectiveness. The cholesterol and long-chain aliphatic amine derivatives were more effective than native G{sub M1}, whereas the phospholipid derivatives were less effective. The distance between G{sub M1}OS and the phospholipid also appeared to influence its functional activity. The results indicate that although G{sub M1}OS provides the recognition site for the binding of cholera toxin, the nature of the lipid moiety plays an important role in the action of the toxin.

  6. Curcumin retunes cholesterol transport homeostasis and inflammation response in M1 macrophage to prevent atherosclerosis.

    Science.gov (United States)

    Chen, Fang-Yuan; Zhou, Juan; Guo, Ning; Ma, Wang-Ge; Huang, Xin; Wang, Huan; Yuan, Zu-Yi

    2015-11-27

    Lipoprotein cholesterol metabolism dysfunction in the arterial wall is a major contributor to atherosclerosis, and excessive lipid intake and failed cholesterol homeostasis may accelerate the atherogenic process. Curcumin exerts multiple effects by alleviating inflammation, hyperlipidemia, and atherosclerosis; however, its role in cholesterol transport homeostasis and its underlying impact on inflammatory M1 macrophages are poorly understood. This work aimed to investigate the effect of curcumin on cholesterol transport, the inflammatory response and cell apoptosis in M1 macrophages. RAW264.7 macrophages (M0) were induced with LPS plus IFN-γ for 12 h to develop a M1 subtype and were then incubated with curcumin at different concentrations (6.25 and 12.5 μmol/L) in the presence or absence of oxLDL. Then, cholesterol influx/efflux and foam cell formation as well as inflammation and apoptosis were evaluated. It was found that curcumin increased cholesterol uptake measured by the Dil-oxLDL binding assay, and simultaneously increased cholesterol efflux carried out by Apo-A1 and HDL in M1 cells. Curcumin further reinforced ox-LDL-induced cholesterol esterification and foam cell formation as determined by Oil Red O and BODIPY staining. Moreover, curcumin dramatically reduced ox-LDL-induced cytokine production such as IL-1β, IL-6 as well as TNF-α and M1 cell apoptosis. We also found that curcumin upregulated CD36 and ABCA1 in M1 macrophages. Curcumin increased PPARγ expression, which in turn promoted CD36 and ABCA1 expression. In conclusion, curcumin may increase the ability of M1 macrophages to handle harmful lipids, thus promoting lipid processing, disposal and removal, which may support cholesterol homeostasis and exert an anti-atherosclerotic effect.

  7. THE RESULTS OF TESTING TO EVALUATE CRYSTAL FORMATION AND SETTLING IN THE COLD CRUCIBLE INDUCTION MELTER

    Energy Technology Data Exchange (ETDEWEB)

    Marra, J.

    2009-06-30

    The Cold Crucible Induction Melter (CCIM) technology offers the potential to increase waste loading for High Level Waste (HLW) glasses leading to significant improvements in waste throughput rates compared to the reference Joule Heated Melter (JHM). Prior to implementation of a CCIM in a production facility it is necessary to better understand processing constraints associated with the CCIM. The glass liquidus temperature requirement for processing in the CCIM is an open issue. Testing was conducted to evaluate crystal formation and crystal settling during processing in the CCIM to gain insight into the effects on processing. A high aluminum/high iron content glass composition with known crystal formation tendencies was selected for testing. A continuous melter test was conducted for approximately 51 hours. To evaluate crystal formation, glass samples were obtained from pours and from glass receipt canisters where the glass melt had varying residence time in the melter. Additionally, upon conclusion of the testing, glass samples from the bottom of the melter were obtained to assess the degree of crystal settling. Glass samples were characterized in an attempt to determine quantitative fractions of crystals in the glass matrix. Crystal identity and relative composition were determined using a combination of x-ray diffraction (XRD) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). Select samples were also analyzed by digesting the glass and determining the composition using inductively coupled atomic emission spectroscopy (ICP-AES). There was evidence of crystal formation (primarily spinels) in the melt and during cooling of the collected glass. There was evidence of crystal settling in the melt over the duration of the melter campaign.

  8. Comparison of BT Settl Model Spectra in NIR to Brown Dwarfs and Massive Exoplanets

    Science.gov (United States)

    Popinchalk, Mark; Buzard, Cam; Alam, Munazza; Camnasio, Sara; Cruz, Kelle L.; Faherty, Jacqueline K.; Rice, Emily L.

    2017-01-01

    Brown dwarfs and giant exoplanets are difficult to observe, which hampers our understanding of their properties. Model spectra, such as the BT Settl model grid, can provide an opportunity to augment and validate our understanding of these faint objects by serving to contrast and complement our analysis of their observed spectra. We present work from an upcoming paper that leverages this opportunity. The near infrared (NIR) wavelength region is favorable for analysis of low mass brown dwarfs and high mass gaseous companions, in particular the K band (1.97 - 2.40 µm) due to its relatively high resolution and high signal-to-noise ratio wavelength range for spectra of planetary companions. We present a method to analyze two regions of the K band spectral structure (2.03 - 2.10 µm and 2.215 - 2.290 µm), and apply it to a sample of objects with field gravity, low gravity, and planetary mass as well as the BT Settl model grid for a similar range of effective temperatures and surface gravities. A correlation between spectral structure and effective temperature is found for the shorter wavelength region and there is evidence of gravity dependence for the longer wavelength range. This work suggests that the K band has the potential to be an indicator for brown dwarf and exoplanet surface gravity and effective temperature. We also present preliminary analysis from another upcoming paper. We examine equivalent widths of K I absorption lines at 1.1693 µm, 1.1773 µm, 1.2436 µm and 1.2525 µm in a selection of L dwarfs to explore their physical properties by comparing them to equivalent measurements in the BT Settl model grid.

  9. The settling velocity of mineral, biomineral, and biological particles and aggregates in water

    Science.gov (United States)

    Maggi, Federico

    2013-04-01

    A new equation was developed to relate the size and settling velocity of particulate matter commonly recurring in aqueous ecosystems. This equation explicitly balanced the gravitational, buoyancy, viscous, and inertial forces as in Rubey () but was amended to describe in one instance both individual particles and granular aggregates with an internal fractal architecture. This approach allowed for an algebraic solution of the settling velocity, thus overcoming earlier approaches that required iterative numerical solutions. The equation was tested with mineral, biomineral, and biological suspended particles and granular aggregates from 52 existing experimental data sets, and resulted in average correlation coefficients R between 71% and 93.9%, and normilized residuals between 14.3% and 24.8% over Reynolds numbers ranging within 10-7 and 102. Accuracy of these results was generally better than for the Stokes' law, the Stokes' law modified with the Schiller-Naumann drag coefficient, and Rubey's equation. Estimated parameters ranged within observed ones, thus suggesting that the equation was robust. An analysis of the drag showed that inertial force was negligible only for biological cells (isolated cysts), whereas it contributed by not less than 5% to the drag on large mineral particles and up to 20% for biomineral and biological aggregates. Finally, a correlation was found between the organic matter content and fractal properties of granular aggregates, which were described by empirical equations proposed here for the first time. The hypothesis that the settling velocity is a function of linear and nonlinear drag, and is ultimately determined by physical characteristics as much as biological composition and internal aggregate geometry, is supported here by quantitative analyses.

  10. Columnar structure formation of a dilute suspension of settling spherical particles in a quiescent fluid

    Science.gov (United States)

    Huisman, Sander G.; Barois, Thomas; Bourgoin, Mickaël; Chouippe, Agathe; Doychev, Todor; Huck, Peter; Morales, Carla E. Bello; Uhlmann, Markus; Volk, Romain

    2016-11-01

    The settling of heavy spherical particles in a column of quiescent fluid is investigated. The performed experiments cover a range of Galileo numbers (110 ≤Ga≤310 ) for a fixed density ratio of Γ =ρp/ρf=2.5 . In this regime the particles are known to show a variety of motions [Jenny, Dušek, and Bouchet, Instabilities and transition of a sphere falling or ascending freely in a Newtonian fluid, J. Fluid Mech. 508, 201 (2004), 10.1017/S0022112004009164]. It is known that the wake undergoes several transitions for increasing Ga resulting in particle motions that are successively vertical, oblique, oblique oscillating, and finally chaotic. Not only does this change the trajectory of single, isolated, settling particles, but it also changes the dynamics of a swarm of particles as collective effects become important even for dilute suspensions with volume fraction up to ΦV=O (10-3) , which are investigated in this work. Multicamera recordings of settling particles are recorded and tracked over time in three dimensions. A variety of analyses are performed and show a strong clustering behavior. The distribution of the cell areas of the Voronoï tessellation in the horizontal plane is compared to that of a random distribution of particles and shows clear clustering. Moreover, a negative correlation was found between the Voronoï area and the particle velocity; clustered particles fall faster. In addition, the angle between adjacent particles and the vertical is calculated and compared to a homogeneous distribution of particles, clear evidence of vertical alignment of particles is found. The experimental findings are compared to simulations.

  11. A comparison of BNR activated sludge systems with membrane and settling tank solid-liquid separation.

    Science.gov (United States)

    Ramphao, M C; Wentzel, M C; Ekama, G A; Alexander, W V

    2006-01-01

    Installing membranes for solid-liquid separation into biological nutrient removal (BNR) activated sludge (AS) systems makes a profound difference not only to the design of the membrane bio-reactor (MBR) BNR system itself, but also to the design approach for the whole wastewater treatment plant (WWTP). In multi-zone BNR systems with membranes in the aerobic reactor and fixed volumes for the anaerobic, anoxic and aerobic zones (i.e. fixed volume fractions), the mass fractions can be controlled (within a range) with the inter-reactor recycle ratios. This zone mass fraction flexibility is a significant advantage of MBR BNR systems over BNR systems with secondary settling tanks (SSTs), because it allows changing the mass fractions to optimise biological N and P removal in conformity with influent wastewater characteristics and the effluent N and P concentrations required. For PWWF/ADWF ratios (fq) in the upper range (fq approximately 2.0), aerobic mass fractions in the lower range (f(maer) settling and long sludge age). However, the volume reduction compared with equivalent BNR systems with SSTs will not be large (40-60%), but the cost of the membranes can be offset against sludge thickening and stabilisation costs. Moving from a flow unbalanced raw wastewater system to a flow balanced (fq = 1) low (usually settled) wastewater strength system can double the ADWF capacity of the biological reactor, but the design approach of the WWTP changes away from extended aeration to include primary sludge stabilisation. The cost of primary sludge treatment then has to be offset against the savings of the increased WWTP capacity.

  12. Effects of rotation on crystal settling in a terrestrial magma ocean: Spherical shell model

    Science.gov (United States)

    Maas, C.; Hansen, U.

    2015-12-01

    Like Moon or Mars, Earth experienced one or several deep magma ocean periods of globalextent in a later stage of its accretion. The crystallization of these magma oceans is of keyimportance for the chemical structure of Earth, the mantle evolution and the onset of platetectonics. Due to the fast rotation of early Earth and the small magma viscosity, rotationprobably had a profound effect on differentiation processes. For example, Matyska et al.[1994] propose that the distribution of heterogeneities like the two large low shear velocityprovinces (LLSVP) at the core mantle boundary is influenced by rotational dynamicsof early Earth. Further Garnero and McNamara [2008] suggest that the LLSVPs arevery long-living anomalies, probably reaching back to the time of differentiation andsolidification of Earth. However, nearly all previous studies neglect the effects of rotation.In our previous work using a Cartesian model, a strong influence of rotation as well asof latitude on the differentiation processes in an early magma ocean was revealed. Weshowed that crystal settling in an early stage of magma ocean crystallization cruciallydepends on latitude as well as on rotational strength and crystal density.In order to overcome the restrictions as to the geometry of the Cartesian model, we arecurrently developing a spherical model to simulate crystal settling in a rotating sphericalshell. This model will allow us not only to investigate crystal settling at the poles andthe equator, but also at latitudes in-between these regions, as well as the migration ofcrystals between poles and equator. ReferencesE. J. Garnero and A. K. McNamara. Structure and dynamics of earth's lower mantle.Science, 320(5876):626-628, 2008.C. Matyska, J. Moser, and D. A. Yuen. The potential influence of radiative heat transferon the formation of megaplumes in the lower mantle. Earth and Planetary ScienceLetters, 125(1):255-266, 1994.

  13. Peroxiredoxin II promotes hepatic tumorigenesis through cooperation with Ras/Forkhead box M1 signaling pathway.

    Science.gov (United States)

    Park, Y-H; Kim, S-U; Kwon, T-H; Kim, J-M; Song, I-S; Shin, H-J; Lee, B-K; Bang, D-H; Lee, S-J; Lee, D-S; Chang, K-T; Kim, B-Y; Yu, D-Y

    2016-07-07

    The current study was carried out to define the involvement of Peroxiredoxin (Prx) II in progression of hepatocellular carcinoma (HCC) and the underlying molecular mechanism(s). Expression and function of Prx II in HCC was determined using H-ras(G12V)-transformed HCC cells (H-ras(G12V)-HCC cells) and the tumor livers from H-ras(G12V)-transgenic (Tg) mice and HCC patients. Prx II was upregulated in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg mouse tumor livers, the expression pattern of which highly similar to that of forkhead Box M1 (FoxM1). Moreover, either knockdown of FoxM1 or site-directed mutagenesis of FoxM1-binding site of Prx II promoter significantly reduced Prx II levels in H-ras(G12V)-HCC cells, indicating FoxM1 as a direct transcription factor of Prx II in HCC. Interestingly, the null mutation of Prx II markedly decreased the number and size of tumors in H-ras(G12V)-Tg livers. Consistent with this, knockdown of Prx II in H-ras(G12V)-HCC cells reduced the expression of cyclin D1, cell proliferation, anchorage-independent growth and tumor formation in athymic nude mice, whereas overexpression of Prx II increased or aggravated the tumor phenotypes. Importantly, the expression of Prx II was correlated with that of FoxM1 in HCC patients. The activation of extracellular signal-related kinase (ERK) pathway and the expression of FoxM1 and cyclin D1 were highly dependent on Prx II in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg livers. Prx II is FoxM1-dependently-expressed antioxidant in HCC and function as an enhancer of Ras(G12V) oncogenic potential in hepatic tumorigenesis through activation of ERK/FoxM1/cyclin D1 cascade.

  14. Consistent dust and gas models for protoplanetary disks. I. Disk shape, dust settling, opacities, and PAHs

    Science.gov (United States)

    Woitke, P.; Min, M.; Pinte, C.; Thi, W.-F.; Kamp, I.; Rab, C.; Anthonioz, F.; Antonellini, S.; Baldovin-Saavedra, C.; Carmona, A.; Dominik, C.; Dionatos, O.; Greaves, J.; Güdel, M.; Ilee, J. D.; Liebhart, A.; Ménard, F.; Rigon, L.; Waters, L. B. F. M.; Aresu, G.; Meijerink, R.; Spaans, M.

    2016-02-01

    We propose a set of standard assumptions for the modelling of Class II and III protoplanetary disks, which includes detailed continuum radiative transfer, thermo-chemical modelling of gas and ice, and line radiative transfer from optical to cm wavelengths. The first paper of this series focuses on the assumptions about the shape of the disk, the dust opacities, dust settling, and polycyclic aromatic hydrocarbons (PAHs). In particular, we propose new standard dust opacities for disk models, we present a simplified treatment of PAHs in radiative equilibrium which is sufficient to reproduce the PAH emission features, and we suggest using a simple yet physically justified treatment of dust settling. We roughly adjust parameters to obtain a model that predicts continuum and line observations that resemble typical multi-wavelength continuum and line observations of Class II T Tauri stars. We systematically study the impact of each model parameter (disk mass, disk extension and shape, dust settling, dust size and opacity, gas/dust ratio, etc.) on all mainstream continuum and line observables, in particular on the SED, mm-slope, continuum visibilities, and emission lines including [OI] 63 μm, high-J CO lines, (sub-)mm CO isotopologue lines, and CO fundamental ro-vibrational lines. We find that evolved dust properties, i.e. large grains, often needed to fit the SED, have important consequences for disk chemistry and heating/cooling balance, leading to stronger near- to far-IR emission lines in general. Strong dust settling and missing disk flaring have similar effects on continuum observations, but opposite effects on far-IR gas emission lines. PAH molecules can efficiently shield the gas from stellar UV radiation because of their strong absorption and negligible scattering opacities in comparison to evolved dust. The observable millimetre-slope of the SED can become significantly more gentle in the case of cold disk midplanes, which we find regularly in our T Tauri models

  15. Flow Quality Surveys in the Settling Chamber of the NASA Glenn Icing Research Tunnel (2011 Tests)

    Science.gov (United States)

    Steen, Laura E.; VanZante, Judith Foss; Broeren, Andy P.; Kubiak, Mark J.

    2014-01-01

    In 2011, the heat exchanger and refrigeration plant for NASA Glenn Research Centers Icing Research Tunnel (IRT) were upgraded. Flow quality surveys were performed in the settling chamber of the IRT in order to understand the effect that the new heat exchanger had on the flow quality upstream of the spray bars. Measurements were made of the total pressure, static pressure, total temperature, airspeed, and flow angle (pitch and yaw). These measurements were directly compared to measurements taken in 2000, after the previous heat exchanger was installed. In general, the flow quality appears to have improved with the new heat exchanger.

  16. Factors controlling the field settling velocity of cohesive sediment in estuaries

    DEFF Research Database (Denmark)

    Pejrup, Morten; Mikkelsen, Ole

    2010-01-01

    this paper expressed as the root mean square [rms] velocity gradient, [G]) in the water on the W-50 in situ. There is a strong need to establish algorithms based on in situ measurements describing the dual impact of both SSC and G on the flocculation process, and hence, W-50. The present paper addresses...... in the correlation of the description of W-50 and the controlling parameters from each area can be obtained. A generic algorithm describing the data from all the investigated areas is suggested. It works well within specific tidal areas but fails to give a generic description of the field settling velocity....

  17. On the Instability of Spheres Settling through a Vertical Pipe Filled with HPG

    OpenAIRE

    Patrick Weidman; Roberts, B.; Eisen, S

    2012-01-01

    An extensive set of experiments were performed to determine the stability boundary for the longitudinal oscillation of steel spheres settling through Hydroxy Propyl Guar (HPG) contained in long vertical tubes, a phenomenon first reported by Mollinger, et al. (1999). Results are reported in d/D-pH parameter space, where d is the sphere diameter and D is the internal diameter of a tube. Longitudinal oscillations, which owe their existence to the self-healing nature of the gel, occur over the re...

  18. Feedforward Compensation by Specified Step Settling Considering Frequency Shaping of Control Input

    Science.gov (United States)

    Hirose, Noriaki; Kawafuku, Motohiro; Iwasaki, Makoto; Hirai, Hiromu

    This paper presents a novel feedforward compensation for the fast and precise positioning control in mechatronic systems. The proposed compensator is designed considering the frequency shaping in control input to suppress the residual vibration, under the constraint of specified step number in position reference. A 2-degrees-of-freedom positioning controller with the proposed feedforward compensation can ensure the required settling performance with the specified steps regardless of the positioning amplitude in reference. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype of galvano scanner.

  19. Mice Lacking M1 and M3 Muscarinic Acetylcholine Receptors Have Impaired Odor Discrimination and Learning

    Science.gov (United States)

    Chan, Wilson; Singh, Sanmeet; Keshav, Taj; Dewan, Ramita; Eberly, Christian; Maurer, Robert; Nunez-Parra, Alexia; Araneda, Ricardo C.

    2017-01-01

    The cholinergic system has extensive projections to the olfactory bulb (OB) where it produces a state-dependent regulation of sensory gating. Previous work has shown a prominent role of muscarinic acetylcholine (ACh) receptors (mAChRs) in regulating the excitability of OB neurons, in particular the M1 receptor. Here, we examined the contribution of M1 and M3 mAChR subtypes to olfactory processing using mice with a genetic deletion of these receptors, the M1−/− and the M1/M3−/− knockout (KO) mice. Genetic ablation of the M1 and M3 mAChRs resulted in a significant deficit in odor discrimination of closely related molecules, including stereoisomers. However, the discrimination of dissimilar molecules, social odors (e.g., urine) and novel object recognition was not affected. In addition the KO mice showed impaired learning in an associative odor-learning task, learning to discriminate odors at a slower rate, indicating that both short and long-term memory is disrupted by mAChR dysfunction. Interestingly, the KO mice exhibited decreased olfactory neurogenesis at younger ages, a deficit that was not maintained in older animals. In older animals, the olfactory deficit could be restored by increasing the number of new born neurons integrated into the OB after exposing them to an olfactory enriched environment, suggesting that muscarinic modulation and adult neurogenesis could be two different mechanism used by the olfactory system to improve olfactory processing. PMID:28210219

  20. Dynamic Changes of Microglia/Macrophage M1 and M2 Polarization in Theiler's Murine Encephalomyelitis.

    Science.gov (United States)

    Herder, Vanessa; Iskandar, Cut Dahlia; Kegler, Kristel; Hansmann, Florian; Elmarabet, Suliman Ahmed; Khan, Muhammad Akram; Kalkuhl, Arno; Deschl, Ulrich; Baumgärtner, Wolfgang; Ulrich, Reiner; Beineke, Andreas

    2015-11-01

    Microglia and macrophages play a central role for demyelination in Theiler's murine encephalomyelitis (TME) virus infection, a commonly used infectious model for chronic-progressive multiple sclerosis. In order to determine the dynamic changes of microglia/macrophage polarization in TME, the spinal cord of Swiss Jim Lambert (SJL) mice was investigated by gene expression profiling and immunofluorescence. Virus persistence and demyelinating leukomyelitis were confirmed by immunohistochemistry and histology. Electron microscopy revealed continuous myelin loss together with abortive myelin repair during the late chronic infection phase indicative of incomplete remyelination. A total of 59 genes out of 151 M1- and M2-related genes were differentially expressed in TME virus-infected mice over the study period. The onset of virus-induced demyelination was associated with a dominating M1 polarization, while mounting M2 polarization of macrophages/microglia together with sustained prominent M1-related gene expression was present during the chronic-progressive phase. Molecular results were confirmed by immunofluorescence, showing an increased spinal cord accumulation of CD16/32(+) M1-, arginase-1(+) M2- and Ym1(+) M2-type cells associated with progressive demyelination. The present study provides a comprehensive database of M1-/M2-related gene expression involved in the initiation and progression of demyelination supporting the hypothesis that perpetuating interaction between virus and macrophages/microglia induces a vicious circle with persistent inflammation and impaired myelin repair in TME.

  1. Reverse phase liquid chromatographic determination and confirmation of aflatoxin M1 in cheese.

    Science.gov (United States)

    Hisada, K; Terada, H; Yamamoto, K; Tsubouchi, H; Sakabe, Y

    1984-01-01

    A systematic method is proposed for determination and confirmation of aflatoxin M1 in cheese by liquid chromatography (LC). A sample of cheese is extracted with chloroform, cleaned up on 2 silica gel columns followed by a Sep-Pak C18 cartridge, and chromatographed on a 5 microns octadecyl silica column with fluorometric detection. The sample extract or standard is treated with n-hexane-trifluoroacetic acid (TFA) (4 + 1) for 30 min at 40 degrees C. Analysis by LC with TFA-treatment of the extract provides quantitative data. Multiple assays of 5 samples of Gouda cheese spiked with aflatoxin M1 at levels of 0.5, 0.1, and 0.05 ng/g showed average recoveries of 93.2, 91.6, and 92.4%, with coefficients of variation of 2.63, 3.97, and 4.52%, respectively. Assay of 5 naturally contaminated cheeses resulted in 0.051-0.448 ng/g of aflatoxin M1. Limit of quantitation is about 0.01 ng/g. The identity of aflatoxin M1 is confirmed by treating aflatoxin M1 or the M2a derivative with TFA-methanol (or ethanol) (3 + 1). The TFA-methanol reaction products of M2a could be detected quantitatively.

  2. E1, M1, E2 transition energies and probabilities of W$^{54+}$ ions

    CERN Document Server

    Ding, Xiao-bin; Liu, Jia-xin; Koike, Fumihiro; Murakami, Izumi; Kato, Daiji; Sakaue, Hiroyuki A; Nakamura, Nobuyuki; Dong, Chen-zhong

    2016-01-01

    A comprehensive theoretical study of the E1, M1, E2 transitions of Ca-like tungsten ions is presented. Using multi-configuration Dirac-Fock (MCDF) method with a restricted active space treatment, the wavelengths and probabilities of the M1 and E2 transitions between the multiplets of the ground state configuration ([Ne]3s$^{2}$3p$^{6}$3d$^{2}$) and of the E1 transitions between [Ne]3s$^{2}$3p$^{5}$3d$^{3}$ and [Ne]3s$^{2}$3p$^{6}$3d$^{2}$ have been calculated. The results are in reasonable agreement with available experimental data. The present E1 and M1 calculations are compared with previous theoretical values. For E2 transitions, the importance of electron correlation from 3s and 3p orbitals is pointed out. Several strong E1 transitions are predicted, which have potential advantage for plasma diagnostics.

  3. M1 muscarinic acetylcholine receptor agonism alters sleep without affecting memory consolidation.

    Science.gov (United States)

    Nissen, Christoph; Power, Ann E; Nofzinger, Eric A; Feige, Bernd; Voderholzer, Ulrich; Kloepfer, Corinna; Waldheim, Bernhard; Radosa, Marc-Philipp; Berger, Mathias; Riemann, Dieter

    2006-11-01

    Preclinical studies have implicated cholinergic neurotransmission, specifically M1 muscarinic acetylcholine receptor (mAChR) activation, in sleep-associated memory consolidation. In the present study, we investigated the effects of administering the direct M1 mAChR agonist RS-86 on pre-post sleep memory consolidation. Twenty healthy human participants were tested in a declarative word-list task and a procedural mirror-tracing task. RS-86 significantly reduced rapid eye movement (REM) sleep latency and slow wave sleep (SWS) duration in comparison with placebo. Presleep acquisition and postsleep recall rates were within the expected ranges. However, recall rates in both tasks were almost identical for the RS-86 and placebo conditions. These results indicate that selective M1 mAChR activation in healthy humans has no clinically relevant effect on pre-post sleep consolidation of declarative or procedural memories at a dose that reduces REM sleep latency and SWS duration.

  4. Attenuation of cocaine's reinforcing and discriminative stimulus effects via muscarinic M1 acetylcholine receptor stimulation

    DEFF Research Database (Denmark)

    Thomsen, Morgane; Conn, P Jeffrey; Lindsley, Craig

    2010-01-01

    Muscarinic cholinergic receptors modulate dopaminergic function in brain pathways thought to mediate cocaine's abuse-related effects. Here, we sought to confirm and extend in the mouse species findings that nonselective muscarinic receptor antagonists can enhance cocaine's discriminative stimulus....... More importantly, we tested the hypothesis that muscarinic receptor agonists with varied receptor subtype selectivity can blunt cocaine's discriminative stimulus and reinforcing effects; we hypothesized a critical role for the M(1) and/or M(4) receptor subtypes in this modulation. Mice were trained...... to discriminate cocaine from saline, or to self-administer intravenous cocaine chronically. The nonselective muscarinic antagonists scopolamine and methylscopolamine, the nonselective muscarinic agonists oxotremorine and pilocarpine, the M(1)/M(4)-preferring agonist xanomeline, the putative M(1)-selective agonist...

  5. Nonlinear {omega}*-stabilization of the m = 1 mode in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, B. [Univ. of Maryland, College Park, MD (United States). Inst. for Plasma Research; Zakharov, L. [Princeton Univ., NJ (United States). Plasma Physics Lab.

    1995-08-01

    Earlier studies of sawtooth oscillations in Tokamak Fusion Test Reactor supershots (Levinton et al, Phys. Rev. Lett. 72, 2895 (1994); Zakharov, et al, Plasma Phys. and Contr. Nucl. Fus. Res., Proc. 15th Int. Conf., Seville 1994, Vienna) have found an apparent contradiction between conventional linear theory and experiment: even in sawtooth-free discharges, the theory typically predicts instability due to a nearly ideal m = 1 mode. Here, the nonlinear evolution of such mode is analyzed using numerical simulations of a two-fluid magnetohydrodynamic (MHD) model. We find the mode saturates nonlinearly at a small amplitude provided the ion and electron drift-frequencies {omega}*{sub i,e} are somewhat above the linear stability threshold of the collisionless m = 1 reconnecting mode. The comparison of the simulation results to m = 1 mode activity in TFTR suggests additional, stabilizing effects outside the present model are also important.

  6. Groundwater quality assessment/corrective action feasibility plan: New TNX Seepage Basin

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, R.L.

    1989-12-05

    The New TNX Seepage Basin is located across River Road east of the TNX Area at the Savannah River Site. Currently the basin is out of service and is awaiting closure in accordance with the Consent Decree settled under Civil Act No. 1:85-2583. Groundwater monitoring data from the detection monitoring network around the New TNX Seepage Basin was recently analyzed using South Carolina Hazardous Waste Management Regulations R.61-79.264.92 methods to determine if groundwater downgradient of the New TNX Seepage Basin had been impacted. Results from the data analysis indicate that the groundwater has been impacted by inorganic constituents with no associated health risks. The impacts resulting from elevated levels of inorganic constituents, such as Mn, Na, and Total PO{sub 4} in the water table, do not pose a threat to human health and the environment.

  7. M1 AFLATOXIN, TOTAL BACTERIAL COUNT AND SOMATIC CELL COUNT IN ORGANIC AND CONVENTIONAL MILK

    Directory of Open Access Journals (Sweden)

    M. Trevisani

    2009-09-01

    Full Text Available Comparative quality evaluation of organic and conventional milk produced in similar environmental condition was performed. Bulk-tank milk was sampled once a week during 30 weeks from 10 organic and 10 conventional dairy farms where aflatoxin M1 level was previous tested during 11 months on bulk-tank milk from tanker at the processing plant. Somatic Cells and Total Microbial Counts did not show differences that can be related to the organic production system, suggesting an effect induced by farm size and technical factors. Higher level of Aflatoxin M1 was found in organic than conventional milk.

  8. Physicochemical characteristics of ambient particles settling upon leaf surfaces of urban plants in Beijing

    Institute of Scientific and Technical Information of China (English)

    WANG Lei; LIU Lian-you; GAO Shang-yu; HASI Eer-dun; WANG Zhi

    2006-01-01

    Particulate pollution is a serious health problem throughout the world, exacerbating a wide range of respiratory and vascular illnesses in urban areas. Urban plants play an important role in reducing particulate pollution. Physicochemical characteristics of ambient particles settling upon leaf surfaces of eleven roadside plants at four sites of Beijing were studies. Results showed that density of particles on the leaf surfaces greatly varied with plant species and traffic condition. Fraxinus chinensis, Sophora japonica, Ailanthus altissima, Syringa oblata and Prunus persica had larger densities of particles among the tall species. Due to resuspension of road dust,the densities of particles ofEuonymus japonicus and Parthenocissus quinquefolia with low sampling height were 2-35 times to other taller tree species. For test plant species, micro-roughness of leaf surfaces and density of particles showed a close correlation. In general, the larger micro-roughness of leaf surfaces is, the larger density of particles is. Particles settling upon leaf surfaces were dominantly PM10 (particulate matter less than 10 μm in aerodynamic diameter; 98.4%) and PM2.5 (particulate matter less than 2.5 μm in aerodynamic diameter; 64.2%) which were closely relative to human health. Constant elements of particles were C, O, K, Ca, Si,earth dust or industrial emission and SO2, H2SO4 or sulfate. NaCl was derived from sea salt.

  9. Consistent dust and gas models for protoplanetary disks. I. Disk shape, dust settling, opacities, and PAHs

    CERN Document Server

    Woitke, P; Pinte, C; Thi, W -F; Kamp, I; Rab, C; Anthonioz, F; Antonellini, S; Baldovin-Saavedra, C; Carmona, A; Dominik, C; Dionatos, O; Greaves, J; Güdel, M; Ilee, J D; Liebhart, A; Ménard, F; Rigon, L; Waters, L B F M; Aresu, G; Meijerink, R; Spaans, M

    2015-01-01

    We propose a set of standard assumptions for the modelling of Class II and III protoplanetary disks, which includes detailed continuum radiative transfer, thermo-chemical modelling of gas and ice, and line radiative transfer from optical to cm wavelengths. We propose new standard dust opacities for disk models, we present a simplified treatment of PAHs sufficient to reproduce the PAH emission features, and we suggest using a simple treatment of dust settling. We roughly adjust parameters to obtain a model that predicts typical Class II T Tauri star continuum and line observations. We systematically study the impact of each model parameter (disk mass, disk extension and shape, dust settling, dust size and opacity, gas/dust ratio, etc.) on all continuum and line observables, in particular on the SED, mm-slope, continuum visibilities, and emission lines including [OI] 63um, high-J CO lines, (sub-)mm CO isotopologue lines, and CO fundamental ro-vibrational lines. We find that evolved dust properties (large grains...

  10. Models of Metal Poor Stars with Gravitational Settling and Radiative Accelerations I. Evolution and Abundance Anomalies

    CERN Document Server

    Richard, O; Richer, J; Turcotte, S; Turck-Chièze, S; Van den Berg, D A; Berg, Don A. Vanden

    2002-01-01

    Evolutionary models have been calculated for Pop II stars of 0.5 to 1.0$M_\\odot$ from the pre-main-sequence to the lower part of the giant branch. Rosseland opacities and radiative accelerations were calculated taking into account the concentration variations of 28 chemical species, including all species contributing to Rosseland opacities in the OPAL tables. The effects of radiative accelerations, thermal diffusion and gravitational settling are included. While models were calculated both for Z=0.00017 and 0.0017, we concentrate on models with Z=0.00017 in this paper. These are the first Pop II models calculated taking radiative acceleration into account. It is shown that, at least in a 0.8$M_\\odot$ star, it is a better approximation not to let Fe diffuse than to calculate its gravitational settling without including the effects of $g_{rad}(Fe)$. In the absence of any turbulence outside of convection zones, the effects of atomic diffusion are large mainly for stars more massive than 0.7$M_\\odot$. Overabundan...

  11. Floc Size and Settling Velocity Observations From Three Contrastingly Different Natural Environments in the USA

    Science.gov (United States)

    Manning, Andrew; Schoellhamer, David; Mehta, Ashish; Nover, Daniel; Schladow, Geoffrey

    2010-05-01

    Environmentally, monitoring the movement of suspended cohesive sediments is highly desirable in both estuaries and lakes. When modelling cohesive sediment transport and mass settling fluxes, the settling speed of the suspended matter is a key parameter. In contrast to purely non-cohesive sandy sediments, mud can flocculate and this poses a serious complication to the modelling of sediment pathways. As flocs grow in size they become more porous and significantly less dense, but their settling speeds continue to rise due to a Stokes' Law relationship. Much research has been conducted on the flocculation characteristics of suspended muddy sediments in saline/brackish tidal conditions, where electrostatic particle bonding can occur. However very little is known about freshwater floc dynamics. This is primarily due to flocs being extremely delicate entities and are thus very difficult to observe in situ. This paper primarily describes a recently developed, portable, low intrusive instrument INSSEV_LF, which permits the direct, in situ measurement of both floc size (D) and settling velocity (Ws), simultaneously. Examples of floc spectra observed from three different environments within the USA are presented and compared. The first site was the turbidity maximum zone in San Francisco Bay, where the suspended solids concentration (SSC) was 170 mg.l-1 and many low density macroflocs up to 400 μm in diameter, settling at speeds of 4-8 mm.s-1 were observed. The second location was the shallow (1.7 m mean depth), freshwater environment of Lake Apopka in Florida. It is highly eutrophic, and demonstrates a turbid SSC of 750 mg.l-1 within a benthic suspension layer. These conditions resulted in D from 45 μm up to 1,875 μm; 80% of the floc were > 160 μm (i.e. macroflocs). Present theories for the settling of flocs rely on fractal theory of self-similarity, but this does not appear to be applicable to the Lake Apopka flocs because they do not possess any basic geometric unit

  12. Chemistry of a protoplanetary disk with grain settling and Lyman alpha radiation

    CERN Document Server

    Fogel, Jeffrey K J; Bergin, Edwin A; Calvet, Nuria; Semenov, Dmitry

    2010-01-01

    We present results from a model of the chemical evolution of protoplanetary disks. In our models we directly calculate the changing propagation and penetration of a high energy radiation field with Lyman alpha radiation included. We also explore the effect on our models of including dust grain settling. We find that, in agreement with earlier studies, the evolution of dust grains plays a large role in determining how deep the UV radiation penetrates into the disk. Significant grain settling at the midplane leads to much smaller freeze-out regions and a correspondingly larger molecular layer, which leads to an increase in column density for molecular species such as CO, CN and SO. The inclusion of Lyman alpha radiation impacts the disk chemistry through specific species that have large photodissociation cross sections at 1216 A. These include HCN, NH3 and CH4, for which the column densities are decreased by an order of magnitude or more due to the presence of Lyman alpha radiation in the UV spectrum. A few spe...

  13. Effect of carbohydrate and protein in the EPS on sludge settling characteristics.

    Science.gov (United States)

    Shin, H S; Kang, S T; Nam, S Y

    2001-01-01

    EPSs have been believed to play a bonding role in microbial floc formation. However, the precise role is not well known. In this study, sludge settling characteristics and the carbohydrate to protein ratio in the EPS were tested at various airflow rates. Sludge was collected from three modified sequencing batch reacetors (MSBRs), which were operated with airflow rates of 0.8 L/min, 2 L/min and 4 L/min, respectively. During the operation periods, the reactor operated at an airflow rate of 0.8 L/min showed a sludge volume index (SVI) of 80 to 90 mL/g and a constant ratio of carbohydrate to protein in the EPS, while a significant increase of this ratio and the SVI occurred in the other reactors. High airflow rate increased the amount of carbohydrate in the EPS, but the protein level was almost constant for reactors with airflow rates of 2 L/min and 4 L/min. The higher ratio of carbohydrate to protein caused the bulking of the sludge; hence it was not favourable for sludge settling. The ratio of carbohydrate and protein in the EPS is inferred to be essential for solid floc formation.

  14. General formulas for drag coefficient and settling velocity of sphere based on theoretical law

    Institute of Scientific and Technical Information of China (English)

    Yang Hongli; Fan Minqiang; Liu Airong; Dong Lianping

    2015-01-01

    The settlement of particles is of great importance in many areas. The accurate determination of drag coefficient and settling velocity in wide Reynolds number (Re) range remains a problem. In this paper, a series of new formulas for drag coefficient of spherical particles based on theoretical laws, such as the Stokes law, the Oseen law, and the Goldstein law, were developed and fitted using 480 groups of experimental data (Re<2 × 105). The results show that the 2nd approximation of a rational function containing only one parameter can describe CD–Re relationship accurately over the whole Re range of 0–2 × 105. The new developed formulas containing five parameters show higher goodness over wide Re range than presently existing equations. The introduction of the Oseen law is helpful for improving the fitting goodness of the empirical formulas. On the basis of one of the Oseen-based CD–Re formulas giving the lowest sum of squared relative errors Q over the whole Re range (Re<2 × 105), a general for-mula for settling velocity ut based on dimensionless parameters was proposed showing high goodness.

  15. Development of a CFD Model for Secondary Final Settling Tanks in Water Pollution Control Plants

    Science.gov (United States)

    Gong, Minwei; Xanthos, Savvas; Ramalingam, Krish; Fillos, John

    2007-11-01

    To assess performance and evaluate alternatives to improve efficiency of the New York City the Wards Island Water Pollution Control Plant (WPCP) FSTs at peak loads, a 3D CFD model has been developed. Fluent was utilized as the base platform, where sub-models of the Suspended Solids (SS), settling characteristics, density currents and SS flocculation were incorporated. This was supplemented by field and bench scale experiments to quantify the coefficients integral to the sub-models. Model calibration and validation have been carried out by using the extensive set of data collected. The model can be used to evaluate different modes of operation, alternate hydraulic and solids loading rates, as well as addition of auxiliary components such as baffles to improve process performance. The model is being used to compare potential benefits for different alternatives of design and operation of the existing FSTs. After comparing series of inlet baffles, a baffle with 4 horizontal and 7 vertical slots has been recommended for installation in the FSTs. Additional baffle type, configurations and locations within the tank are also being evaluated to improve the performance of the FSTs especially during periods of poor settling and peak flow conditions.

  16. Recent Development of QCD Factorization for B-> M1 M2

    CERN Document Server

    Yang, Deshan

    2010-01-01

    After briefly introducing the framework of QCD factorization for B-> M1 M2 in the language of the Soft-Collinear Effective Theory, we firstly address the recent efforts on higher-order radiative corrections in QCD factorization. Then we discuss some phenomenologies in B-> V V within the framework of QCD factorization.

  17. 26 CFR 31.3306(m)-1 - American vessel and aircraft.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 15 2010-04-01 2010-04-01 false American vessel and aircraft. 31.3306(m)-1... vessel and aircraft. (a) The term “American vessel” means any vessel which is documented (that is....) (b) The term “American aircraft” means any aircraft registered under the laws of the United States...

  18. M1 corticospinal mirror neurons and their role in movement suppression during action observation.

    Science.gov (United States)

    Vigneswaran, Ganesh; Philipp, Roland; Lemon, Roger N; Kraskov, Alexander

    2013-02-04

    Evidence is accumulating that neurons in primary motor cortex (M1) respond during action observation, a property first shown for mirror neurons in monkey premotor cortex. We now show for the first time that the discharge of a major class of M1 output neuron, the pyramidal tract neuron (PTN), is modulated during observation of precision grip by a human experimenter. We recorded 132 PTNs in the hand area of two adult macaques, of which 65 (49%) showed mirror-like activity. Many (38 of 65) increased their discharge during observation (facilitation-type mirror neuron), but a substantial number (27 of 65) exhibited reduced discharge or stopped firing (suppression-type). Simultaneous recordings from arm, hand, and digit muscles confirmed the complete absence of detectable muscle activity during observation. We compared the discharge of the same population of neurons during active grasp by the monkeys. We found that facilitation neurons were only half as active for action observation as for action execution, and that suppression neurons reversed their activity pattern and were actually facilitated during execution. Thus, although many M1 output neurons are active during action observation, M1 direct input to spinal circuitry is either reduced or abolished and may not be sufficient to produce overt muscle activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. A fluorescence anisotropy assay for the muscarinic M1 G-protein-coupled receptor.

    Science.gov (United States)

    Huwiler, Kristin G; De Rosier, Therese; Hanson, Bonnie; Vogel, Kurt W

    2010-06-01

    In the search for new chemical entities that interact with G-proteincoupled receptors (GPCRs), assays that quantify efficacy and affinity are employed. Traditional methods for measuring affinity involve radiolabeled ligands. To address the need for homogeneous biochemical fluorescent assays to characterize orthosteric ligand affinity and dissociation rates, we have developed a fluorescence anisotropy (FA) assay for the muscarinic M1 receptor that can be conducted in a 384-well plate. We used membranes from a muscarinic M1 cell line optimized for high-throughput functional assays and the previously characterized fluorescent antagonist BODIPY FL pirenzepine. The affinities of reference compounds were determined in the competitive FA assay and compared with those obtained with a competitive filter-based radioligand-binding assay using [(3)H] N-methylscopolamine. The IC(50) values produced from the FA assay were well-correlated with the radioligand-binding K(i) values (R(2) = 0.98). The dissociation of the BODIPY FL pirenzepine was readily monitored in real time using the FA assay and was sensitive to the presence of the allosteric modulator gallamine. This M1 FA assay offers advantages over traditional radioligandbinding assays as it eliminates radioactivity while allowing investigation of orthosteric or allosteric muscarinic M1 ligands in a homogeneous format.

  20. Stereospecific reduction of virginiamycin M1 as the virginiamycin resistance pathway in Streptomyces virginiae.

    Science.gov (United States)

    Lee, C K; Minami, M; Sakuda, S; Nihira, T; Yamada, Y

    1996-03-01

    In a cell extract of Streptomyces virginiae, virginiamycin M1 was inactivated in the presence of NADPH, while virginiamycin S remained intact. The inactivated product of virginiamycin M1 was isolated, and structure analysis revealed that the inactivation involves reduction of a C-16 carbonyl group leading to the formation of 16-dihydrovirginiamycin M1. Acetonide and benzylidene acetal derivatives were synthesized from the two hydroxyl groups on C-14 and C-16, and the C-16 stereochemistry was determined by 13C nuclear magnetic resonance spectroscopy. Two methyl groups of the acetonide derivative gave 13C signals of 20.1 and 30.1 ppm, indicating that the relative stereochemistry of the C-14 and C-16 hydroxy groups is syn. Furthermore, irradiation of the benzylidene methine proton gave clear nuclear Overhauser effect enhancement of the C-14 or C-16 methine protons, indicating that H-14 and H-16 were in an axial configuration. From the (14S) absolute configuration of natural virginiamycin M1 and the syn relative configuration for the C-14 and C-16 hydroxyl groups of the inactivated product, the C-16 absolute configuration of the inactivated product was thus identified as R.

  1. Multiple outflows in the bipolar planetary nebula M1-16: A molecular line study

    NARCIS (Netherlands)

    Sahai, Raghvendra; Wootten, Alwyn; Schwarz, Hugo E.; Wild, W.

    1994-01-01

    Extensive observations of the molecular gas in the young, compact planetary nebula M1-16 have been made, using the Swedish-ESO-Submillimeter Telescope. A map of the CO J = 2-1 emission shows that the molecular envelope contains both a slow and a fast outflow with expansion velocities of 19 km/s and

  2. Molecular mechanisms that regulate the macrophage M1/M2 polarization balance

    Directory of Open Access Journals (Sweden)

    Nan eWang

    2014-11-01

    Full Text Available As an essential component of innate immunity, macrophages have multiple functions in both inhibiting or promoting cell proliferation and tissue repair. Diversity and plasticity are hallmarks of macrophages. Classical M1 and alternative M2 activation of macrophages, mirroring the Th1–Th2 polarization of T cells, represent two extremes of a dynamic changing state of macrophage activation. M1-type macrophages release cytokines that inhibit the proliferation of surrounding cells and damage contiguous tissue, and M2-type macrophages release cytokines that promote the proliferation of contiguous cells and tissue repair. M1-M2 polarization of macrophage is a tightly controlled process entailing a set of signaling pathways, transcriptional and posttranscriptional regulatory networks. An imbalance of macrophage M1-M2 polarization is often associated with various diseases or inflammatory conditions. Therefore identification of the molecules associated with the dynamic changes of macrophage polarization and understanding their interactions is crucial for elucidating the molecular basis of disease progression and designing novel macrophage-mediated therapeutic strategies.

  3. A Busy period analysis for the state dependent M/M/1/K queue

    NARCIS (Netherlands)

    Al Hanbali, Ahmad; Boxma, Onno

    2010-01-01

    In this paper, we study the transient behavior of a state dependent M/M/1/K queue during the busy period. We derive in closed-form the joint transform of the length of the busy period, the number of customers served during the busy period, and the number of losses during the busy period. For two

  4. Aflatoxin M1 in raw milk and binding of aflatoxin by lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Aflatoxin M1 in raw milk and binding of aflatoxin by lactic acid bacteria

    2010-12-01

    Full Text Available Aflatoxin M1 (AFM1 is potential human carcinogen. Its presence in milk and dairy products represents risk for human health. Therefore, this study was carried out in order to determine thedegree of microbiological contamination by mold, and the potential presence of aflatoxin M1 in 60 raw milk samples, randomly taken from individual producers from different regions of the continental Croatia. The most common genera isolated fungi were Geotrichum (78.3 %, Aspergillus (32.4 % and Penicillium (27.0 %. From total of 60 studied milk samples, 86.66 % were positive for the presence of aflatoxin M1, and 6.66 % of samples were above the prescribed limits. Lactic acid bacteria used in fermented dairy products as a starter culture may play a role in reduction of aflatoxin in foods and nutrients. In this paper the ability of lactic acid bacteria: Lactobacillus rhamnosus GG (ATCC 53103, Lactobacillus delbrueckii S1 and Lactobacillus plantarum A1 to bind aflatoxin M1 was investigated. Standard strain L. rhamnosus GG (ATCC 53103 and L. delbrueckii S1 can significantly (P50 % compared to L. plantarum A1, which binds AFM1 between 18.7 to 28.7 %.

  5. Chlorogenic acid inhibits glioblastoma growth through repolarizating macrophage from M2 to M1 phenotype

    Science.gov (United States)

    Xue, Nina; Zhou, Qin; Ji, Ming; Jin, Jing; Lai, Fangfang; Chen, Ju; Zhang, Mengtian; Jia, Jing; Yang, Huarong; Zhang, Jie; Li, Wenbin; Jiang, Jiandong; Chen, Xiaoguang

    2017-01-01

    Glioblastoma is an aggressive tumor that is associated with distinctive infiltrating microglia/macrophages populations. Previous studies demonstrated that chlorogenic acid (5-caffeoylquinic acid, CHA), a phenolic compound with low molecular weight, has an anti-tumor effect in multiple malignant tumors. In the present study, we focused on the macrophage polarization to investigate the molecular mechanisms behind the anti-glioma response of CHA in vitro and in vivo. We found that CHA treatment increased the expression of M1 markers induced by LPS/IFNγ, including iNOS, MHC II (I-A/I-E subregions) and CD11c, and reduced the expression of M2 markers Arg and CD206 induced by IL-4, resulting in promoting the production of apoptotic-like cancer cells and inhibiting the growth of tumor cells by co-culture experiments. The activations of STAT1 and STAT6, which are two crucial signaling events in M1 and M2-polarization, were significantly promoted and suppressed by CHA in macrophages, respectively. Furthermore, In G422 xenograft mice, CHA increased the proportion of CD11c-positive M1 macrophages and decreased the distribution of CD206-positive M2 macrophages in tumor tissue, consistent with the reduction of tumor weight observed in CHA-treated mice. Overall these findings indicated CHA as a potential therapeutic approach to reduce glioma growth through promoting M1-polarized macrophage and inhibiting M2 phenotypic macrophage. PMID:28045028

  6. Tim-3 promotes intestinal homeostasis in DSS colitis by inhibiting M1 polarization of macrophages.

    Science.gov (United States)

    Jiang, Xingwei; Yu, Jiahui; Shi, Qingzhu; Xiao, Yan; Wang, Wei; Chen, Guojiang; Zhao, Zhi; Wang, Renxi; Xiao, He; Hou, Chunmei; Feng, Jiannan; Ma, Yuanfang; Shen, Beifen; Wang, Lili; Li, Yan; Han, Gencheng

    2015-10-01

    Tim-3 is involved in the physiopathology of inflammatory bowel disease (IBD), but the underlying mechanism is unknown. Here, we demonstrated that, in mouse with DSS colitis, Tim-3 inhibited the polarization of pathogenic pro-inflammatory M1 macrophages, while Tim-3 downregulation or blockade resulted in an increased M1 response. Adoptive transfer of Tim-3-silenced macrophages worsened DSS colitis and enhanced inflammation, while Tim-3 overexpression attenuated DSS colitis by decreasing the M1 macrophage response. Co-culture of Tim-3-overexpressing macrophages with intestinal lymphocytes decreased the pro-inflammatory response. Tim-3 shaped intestinal macrophage polarization may be TLR-4 dependent since Tim-3 blockade failed to exacerbate colitis or increase M1 macrophage response in the TLR-4 KO model. Finally, Tim-3 signaling inhibited phosphorylation of IRF3, a TLR-4 downstream transcriptional factor regulating macrophage polarization. A better understanding of this pathway may shed new light on colitis pathogenesis and result in a new therapeutic strategy.

  7. Experimental Conditions: SE18_S1_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available liver and brain by Orbitrap MS and automated search engine Lipid Search SE18_S1 Mouse liver SE18_S1_M1 34.1...phy. SE18_MS1 Preparation of lipid extract and ESI negative detection by LC-MS analysis SE18_DS1 Identification of phospholipids with Lipid Search default ...

  8. Experimental Conditions: SE18_S2_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available liver and brain by Orbitrap MS and automated search engine Lipid Search SE18_S2 Mouse brain SE18_S2_M1 10.8...phy. SE18_MS1 Preparation of lipid extract and ESI negative detection by LC-MS analysis SE18_DS1 Identification of phospholipids with Lipid Search default ...

  9. Design of an E-ELT M1 segment measurement machine with nanometer accuracy

    NARCIS (Netherlands)

    Bos, A.; Henselmans, R.; Rosielle, P.C.J.N.; Steinbuch, M.; Voert, M.J.A. te

    2014-01-01

    The baseline design of the European Extremely Large Telescope features a telescope with a 39-meter-class primary mirror (M1), consisting of 798 hexagonal segments. A measurement machine design is presented based on a non-contact single-point scanning technique, capable of measuring the form error of

  10. Experimental Conditions: SE37_S16_M1_D1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available opes SE37_S16 Blank (80% methanol) SE37_S16_M1 0mg [MassBase ID] MDLC1_43484 SE37_MS1 Metabolites extraction... with 80% methanol and analysis by LC-Orbitrap-MS SE37_DS1 Peak extraction for unlabeled data 6|ITMS 2 ...

  11. Multiple outflows in the bipolar planetary nebula M1-16: A molecular line study

    NARCIS (Netherlands)

    Sahai, Raghvendra; Wootten, Alwyn; Schwarz, Hugo E.; Wild, W.

    1994-01-01

    Extensive observations of the molecular gas in the young, compact planetary nebula M1-16 have been made, using the Swedish-ESO-Submillimeter Telescope. A map of the CO J = 2-1 emission shows that the molecular envelope contains both a slow and a fast outflow with expansion velocities of 19 km/s and

  12. Aflatoxin M1 in white cheese and butter consumed in Istanbul, Turkey.

    Science.gov (United States)

    Aycicek, Hasan; Yarsan, Ender; Sarimehmetoglu, Belgin; Cakmak, Omer

    2002-10-01

    We studied the occurrence of Aflatoxin M1 (AFM1) in 183 sample of white cheese and butter in Istanbul, Turkey in 2001. The incidence of AFM1 in white cheese and butter samples was as high as 65 and 81, respectively. The particularly high AFM,concentrations imply that more importance should be given to routine analysis of these dairy products.

  13. Effects on Variations in M1 Generation of Durum Wheat (T. durum Thell by Induced Mutagen

    Directory of Open Access Journals (Sweden)

    O. Bilgin

    2005-01-01

    Full Text Available In this research conducted ın Department of Field Crops, Tekirdağ Agricultural Faculty, TrakyaUniversity, the effect of six different gamma ray doses on plant growth in M1 generations derived from twodurum wheat cultivars was investigated.In the experiment, 10 plants in each pot (17 x 40 cm containing 5 kgsoil were grown with three replicates. Total 30 plants for each treatment were used. In M1 generation, numberof leaves, number of roots, seedling height, seedling weight, leaf weight and germination rate were determined.Application of 100-200 gray gamma ray doses did not have any inhibitory effect on investigated characters inseedling growth of M1 generation. On the other hand, 400-500 gray doses significantly inhibited the plantgrowth. 100-200 gray doses did not affect the seed germination rate whereas germination rate decreased with400-500 gray gamma ray applications. At 600 gray dose, only one seed remained viably, rest of them could notsurvive. It was generally observed the highest variations at 300-400 gray gamma doses in M1 plants.

  14. Intravirion cohesion of matrix protein M1 with ribonucleocapsid is a prerequisite of influenza virus infectivity.

    Science.gov (United States)

    Zhirnov, O P; Manykin, A A; Rossman, J S; Klenk, H D

    2016-05-01

    Influenza virus has two major structural modules, an external lipid envelope and an internal ribonucleocapsid containing the genomic RNA in the form of the ribonucleoprotein (RNP) complex, both of which are interlinked by the matrix protein M1. Here we studied M1-RNP cohesion within virus exposed to acidic pH in vitro. The effect of acidification was dependent on the cleavage of the surface glycoprotein HA. Acidic pH caused a loss of intravirion RNP-M1 cohesion and activated RNP polymerase activity in virus with cleaved HA (HA1/2) but not in the uncleaved (HA0) virus. The in vitro acidified HA1/2 virus rapidly lost infectivity whereas the HA0 one retained infectivity, following activation by trypsin, suggesting that premature activation and release of the RNP is detrimental to viral infectivity. Rimantadine, an inhibitor of the M2 ion channel, was found to protect the HA1/2 virus interior against acidic disintegration, confirming that M2-dependent proton translocation is essential for the intravirion RNP release and suggesting that the M2 ion channel is only active in virions with cleaved HA. Acidic treatment of both HA0 and HA1/2 influenza viruses induces formation of spikeless bleb-like protrusion of ~ 25 nm in diameter on the surface of the virion, though only the HA1/2 virus was permeable to protons and permitted RNP release. It is likely that this bleb corresponds to the M2-enriched and M1-depleted focus arising from pinching off of the virus during the completion of budding. Cooperatively, the data suggest that the influenza virus has an asymmetric structure where the M1-mediated organization of the RNP inside the virion is a prerequisite for infectious entry into target cell. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Increased SMA-M1 coherence in Parkinson's disease - Pathophysiology or compensation?

    Science.gov (United States)

    Pollok, Bettina; Kamp, Daniel; Butz, Markus; Wojtecki, Lars; Timmermann, Lars; Südmeyer, Martin; Krause, Vanessa; Schnitzler, Alfons

    2013-09-01

    Parkinson's disease (PD) is a common neurodegenerative disorder owing to loss of dopaminergic cells. Akinesia - one of the core symptoms of PD - is associated with exaggerated oscillations at beta frequency (13-30 Hz) within the subthalamic nucleus (STN). Thus, enhanced oscillations below 30 Hz are assumed to represent a pathophysiological marker of PD. However, recent data suggest that OFF medication exaggerated beta oscillations within basal ganglia (BG) cortical networks may serve for the compensation of BG dysfunctions. The STN is functionally connected to mesial prefrontal areas like the supplementary motor area (SMA). But, it is still not fully understood how enhanced beta oscillations within the BG exert dominance over the primary motor cortex (M1) thereby yielding motor impairment. The present study, therefore, investigates the effect of dopaminergic state on SMA-M1 functional connectivity using Magnetoencephalography (MEG). MEG data were recorded in 7 patients suffering from PD with preponderance of akinesia during isometric contraction of the right forearm and during rest. Coherence as a measure of functional connectivity between M1 and SMA was calculated OFF and ON medication and correlated with the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS III) and with disease duration. During rest a significant positive correlation between disease duration and SMA-M1 coherence was found ON but not OFF medication. Conversely, during isometric contraction SMA-M1 coherence and UPDRS III were inversely correlated OFF but not ON medication explaining more than 80% of variance. The results favor the hypothesis that OFF medication exaggerated cortical coherence at beta frequency represents a compensatory mechanism rather than a pathophysiological marker per se. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Balancing the excitability of M1 circuitry during movement observation without overt replication

    Directory of Open Access Journals (Sweden)

    Pablo eArias

    2014-09-01

    Full Text Available Although observation of a movement increases the excitability of the motor system of the observer, it does not induce a motor replica. What is the mechanism for replica suppression? We performed a series of experiments, involving a total of 66 healthy humans, to explore the excitability of different M1 circuits and the spinal cord during observation of simple movements. Several strategies were used. In the first and second experimental blocks, we used several delay times from movement onset to evaluate the time-course modulation of the cortico-spinal excitability (CSE, and its potential dependency on the duration of the movement observed; in order to do this single pulse transcranial magnetic stimulation (TMS over M1 was used. In subsequent experiments, at selected delay times from movement-onset, we probed the excitability of the cortico-spinal circuits using three different approaches: i electric cervicomedullary stimulation, to test spinal excitability, ii paired-pulse TMS over M1, to evaluate the cortical inhibitory-excitatory balance (short intracortical inhibition SICI and intracortical facilitation ICF and iii continuous theta-burst stimulation (cTBS, to modulate the excitability of M1cortical circuits. We observed a stereotyped response in the modulation of CSE. At 500ms after movement-onset the ICF was increased; although the most clear-cut effect was a decrease of CSE. The compensatory mechanism was not explained by changes in SICI, but by M1-intracortical circuits targeted by cTBS. Meanwhile, the spinal cord maintained the elevated level of excitability induced when expecting to observe movements, potentially useful to facilitate any required response to the movement observed.

  17. Effect of particle volume fraction on the settling velocity of volcanic ash particles: insights from joint experimental and numerical simulations

    Science.gov (United States)

    Del Bello, Elisabetta; Taddeucci, Jacopo; de’ Michieli Vitturi, Mattia; Scarlato, Piergiorgio; Andronico, Daniele; Scollo, Simona; Kueppers, Ulrich; Ricci, Tullio

    2017-01-01

    Most of the current ash transport and dispersion models neglect particle-fluid (two-way) and particle-fluid plus particle-particle (four-way) reciprocal interactions during particle fallout from volcanic plumes. These interactions, a function of particle concentration in the plume, could play an important role, explaining, for example, discrepancies between observed and modelled ash deposits. Aiming at a more accurate prediction of volcanic ash dispersal and sedimentation, the settling of ash particles at particle volume fractions (ϕp) ranging 10‑7-10‑3 was performed in laboratory experiments and reproduced by numerical simulations that take into account first the two-way and then the four-way coupling. Results show that the velocity of particles settling together can exceed the velocity of particles settling individually by up to 4 times for ϕp ~ 10‑3. Comparisons between experimental and simulation results reveal that, during the sedimentation process, the settling velocity is largely enhanced by particle-fluid interactions but partly hindered by particle-particle interactions with increasing ϕp. Combining the experimental and numerical results, we provide an empirical model allowing correction of the settling velocity of particles of any size, density, and shape, as a function of ϕp. These corrections will impact volcanic plume modelling results as well as remote sensing retrieval techniques for plume parameters.

  18. Effect of particle volume fraction on the settling velocity of volcanic ash particles: insights from joint experimental and numerical simulations

    Science.gov (United States)

    Del Bello, Elisabetta; Taddeucci, Jacopo; de’ Michieli Vitturi, Mattia; Scarlato, Piergiorgio; Andronico, Daniele; Scollo, Simona; Kueppers, Ulrich; Ricci, Tullio

    2017-01-01

    Most of the current ash transport and dispersion models neglect particle-fluid (two-way) and particle-fluid plus particle-particle (four-way) reciprocal interactions during particle fallout from volcanic plumes. These interactions, a function of particle concentration in the plume, could play an important role, explaining, for example, discrepancies between observed and modelled ash deposits. Aiming at a more accurate prediction of volcanic ash dispersal and sedimentation, the settling of ash particles at particle volume fractions (ϕp) ranging 10−7-10−3 was performed in laboratory experiments and reproduced by numerical simulations that take into account first the two-way and then the four-way coupling. Results show that the velocity of particles settling together can exceed the velocity of particles settling individually by up to 4 times for ϕp ~ 10−3. Comparisons between experimental and simulation results reveal that, during the sedimentation process, the settling velocity is largely enhanced by particle-fluid interactions but partly hindered by particle-particle interactions with increasing ϕp. Combining the experimental and numerical results, we provide an empirical model allowing correction of the settling velocity of particles of any size, density, and shape, as a function of ϕp. These corrections will impact volcanic plume modelling results as well as remote sensing retrieval techniques for plume parameters. PMID:28045056

  19. Effects of Deer Settling Stimulus and Deer Density on Regeneration in a Harvested Southern New England Forest

    Directory of Open Access Journals (Sweden)

    Kevin J. Barrett

    2013-01-01

    Full Text Available Elevated deer densities have led to reports of forest regeneration failure and ecological damage. However, there is growing evidence that the biophysical conditions of a forest that make it attractive to deer may be a contributing factor in determining browsing levels. Thus, an understanding of settling stimulus—how attractive an area is to deer in terms of food-independent habitat requirements—is potentially important to manage deer browsing impacts. We tested the settling stimulus hypothesis by evaluating the degree to which thermal settling stimulus and deer density are related to spatial variation in browsing intensity across different forest harvesting strategies over the course of a year. We determined if deer were impacting plant communities and if they resulted in changes in plant cover. We quantified the thermal environment around each harvest and tested to see if it influenced deer density and browsing impact. We found that deer had an impact on the landscape but did not alter plant cover or diminish forest regeneration capacity. Deer density and browse impact had a relationship with thermal settling stimulus for summer and fall months, and deer density had a relationship with browse impact in the winter on woody plants. We conclude that thermal settling stimulus is an important predictor for deer density and browsing impact.

  20. Test of the MarsSedEx Settling Tube Photometer during the 2nd Swiss Parabolic Flight Campaign

    Science.gov (United States)

    Kuhn, Nikolaus J.; Kuhn, Brigitte; Rüegg, Hans-Rudolf; Zimmermann, Lukas

    2017-04-01

    Gravity affects flow hydraulics and thus limits the application of simple models for sediment transport developed for Earth on Mars. The significance of the differences in sediment settling has been demonstrated for sand-sized particles by measuring settling velocities using video-imaging during parabolic flights. This approach does not work for finer particles because they cannot be distinguished individually on a video. Tracking of fine sediment clouds is also difficult using videos because changes in density are not captured. Photometers, on the other hand, are able to capture differences in turbidity and offer the potential to measure the settling behaviour of clouds of fine and differently-sized sediment particles. In this study, the feasibility of using a settling-tube photometer used for the rapid assessment of settling velocities developed by the University of Basel during a parabolic flight with reduced gravity is presented. In addition, the potential of the results generated in this Martian-analogue environment to support the identification sediments containing traces of life on Mars is discussed.

  1. Suspended clays and silts: Are they independent or dependent fractions when it comes to settling in a turbulent suspension*

    Science.gov (United States)

    Tran, Duc; Strom, Kyle

    2017-04-01

    This research examines whether or not mixes of clay and silt in a turbulent suspension act and settle independent of each other. More specifically, we examine the following three questions: (1) does the presence of silt in suspension alter the size of mud flocs relative to those from a pure clay suspension of equivalent concentration* (2) can silt particles become bound inside clay flocs*; and (3) if silt is bound within flocs, how does this change the settling properties of the clay and silt mixture* These questions are explored through a series of laboratory experiments in which: (a) images of flocs and silt particles within the turbulent suspension are used to measure their size distribution as a function of time; and (b) the settling velocity of the individual aggregates from each of the suspensions are measured in a settling column. The experiments use pure clay, pure silt, and two different mixture ratios of silt and clay. The results show three primary conclusions. First, the presence of silt has no significant impact on floc size. Second, most of the silt in suspension became bound up within the floc aggregates. And third, the bound silt within the flocs increased the floc settling velocity by at least 50%. These results have potential implications for the modeling of suspended mud mixtures in rivers, estuaries, and turbidity currents.

  2. An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Phillip A.; Wells, Beric E.; Fort, James A.; Meyer, Perry A.

    2009-05-22

    The Hanford Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify a large portion of the waste in Hanford’s 177 underground waste storage tanks. Numerous process vessels will hold waste at various stages in the WTP. Some of these vessels have mixing-system requirements to maintain conditions where the accumulation of hydrogen gas stays below acceptable limits, and the mixing within the vessels is sufficient to release hydrogen gas under normal conditions and during off-normal events. Some of the WTP process streams are slurries of solid particles suspended in Newtonian fluids that behave as non-Newtonian slurries, such as Bingham yield-stress fluids. When these slurries are contained in the process vessels, the particles can settle and become progressively more concentrated toward the bottom of the vessels, depending on the effectiveness of the mixing system. One limiting behavior is a settled layer beneath a particle-free liquid layer. The settled layer, or any region with sufficiently high solids concentration, will exhibit non-Newtonian rheology where it is possible for the settled slurry to behave as a soft solid with a yield stress. In this report, these slurries are described as settling cohesive slurries.

  3. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates.

    Science.gov (United States)

    Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P Ryan; Murphy, Elizabeth A; Garcia, Marcelo H

    2015-01-01

    Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study

  4. A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates.

    Directory of Open Access Journals (Sweden)

    Tatiana Garcia

    Full Text Available Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this

  5. Immunohistochemical localisation of cholinergic muscarinic receptor subtype 1 (M1r) in the guinea pig and human enteric nervous system.

    Science.gov (United States)

    Harrington, A M; Hutson, J M; Southwell, B R

    2007-07-01

    Little is known regarding the location of cholinergic muscarinic receptor 1 (M1r) in the ENS, even though physiological data suggest that M1rs are central to cholinergic neurotransmission. This study localised M1rs in the ENS of the guinea pig ileum and human colon using fluorescence immunohistochemistry and RT-PCR in human colon. Double labelling using antibodies against neurochemical markers was used to identify neuron subytpes bearing M1r. M1r immunoreactivity (IR) was present on neurons in the myenteric and submucosal ganglia. The two antibodies gave similar M1r-IR patterns and M1r-IR was abolished upon antibody preabsorption. M1r-IR was present on cholinergic and nNOS-IR nerve cell bodies in both guinea pig and human myenteric neurons. Presynaptic M1r-IR was present on NOS-IR and VAChT-IR nerve fibres in the circular muscle in the human colon. In the submucosal ganglia, M1r-IR was present on a population of neurons that contained cChAT-IR, but did not contain NPY-IR or calretinin-IR. M1r-IR was present on endothelial cells of blood vessels in the submucosal plexus. The localisation of M1r-IR in the guinea pig and human ENS shown in this study agrees with physiological studies. M1r-IR in cholinergic and nitrergic neurons and nerve fibres indicate that M1rs have a role in both cholinergic and nitrergic transmission. M1r-IR present in submucosal neurons suggests a role in mediating acetylcholine's effect on submucosal sensory and secretomotor/vasodilator neurons. M1r-IR present on blood vessel endothelial cells suggests that M1rs may also mediate acetylcholine's direct effect on vasoactivation.

  6. The Reaction Dynamics of the Reactions Ba+CmH2m+1Br(m=1,2,3,4,5)

    Institute of Scientific and Technical Information of China (English)

    韩克利; 郑锡光; 张瑞勤; 孙本繁; 何国钟; 楼南泉

    1994-01-01

    The internal energy distributions of the nascent BaBr products formed in the reactions ofBa+BrR(R=CH3,C2H5,C3H7,C4H9,C5H11) under the single collision condition have been first studied bylaser-induced fluorescence method.With computer simulations of the experimental spectra,we obtained thevibrational distributions of the BaBr products,and found that the vibrational excitation and reaction cross-section increase with the number of the carbon atoms in the alkyl radical R.The quasitriatomic LEPS poten-tial of the Ba+CH3 reaction has been deduced reversely from the experimental results.The dynamics of thereactions Ba+BrR have been studied by the classical trajectory calculations based on the model LEPS poten-tials.It is concluded that the mass factor and the C-Br bond strength are the major factors affecting the rela-tionship between vibrational excitation and reaction cross-section with the number of the carbon atoms in thealkyl radical R.Furthermore,we obtained all the LEPS potentials of the reactive systems Ba+CmH2m+1 andconfirmed its reliability with ab initio calculations.

  7. Intravirion cohesion of matrix protein M1 with ribonucleocapsid is a prerequisite of influenza virus infectivity

    Energy Technology Data Exchange (ETDEWEB)

    Zhirnov, O.P., E-mail: zhirnov@inbox.ru [D.I. Ivanovsky Institute of Virology, Moscow 123098 (Russian Federation); Manykin, A.A. [D.I. Ivanovsky Institute of Virology, Moscow 123098 (Russian Federation); Rossman, J.S. [School of Biosciences, University of Kent, Canterbury CT27NJ (United Kingdom); Klenk, H.D. [Institute of Virology, Philipps University, Marburg 35037 (Germany)

    2016-05-15

    Influenza virus has two major structural modules, an external lipid envelope and an internal ribonucleocapsid containing the genomic RNA in the form of the ribonucleoprotein (RNP) complex, both of which are interlinked by the matrix protein M1. Here we studied M1-RNP cohesion within virus exposed to acidic pH in vitro. The effect of acidification was dependent on the cleavage of the surface glycoprotein HA. Acidic pH caused a loss of intravirion RNP-M1 cohesion and activated RNP polymerase activity in virus with cleaved HA (HA1/2) but not in the uncleaved (HA0) virus. The in vitro acidified HA1/2 virus rapidly lost infectivity whereas the HA0 one retained infectivity, following activation by trypsin, suggesting that premature activation and release of the RNP is detrimental to viral infectivity. Rimantadine, an inhibitor of the M2 ion channel, was found to protect the HA1/2 virus interior against acidic disintegration, confirming that M2-dependent proton translocation is essential for the intravirion RNP release and suggesting that the M2 ion channel is only active in virions with cleaved HA. Acidic treatment of both HA0 and HA1/2 influenza viruses induces formation of spikeless bleb-like protrusion of ~25 nm in diameter on the surface of the virion, though only the HA1/2 virus was permeable to protons and permitted RNP release. It is likely that this bleb corresponds to the M2-enriched and M1-depleted focus arising from pinching off of the virus during the completion of budding. Cooperatively, the data suggest that the influenza virus has an asymmetric structure where the M1-mediated organization of the RNP inside the virion is a prerequisite for infectious entry into target cell. - Highlights: • The influenza A virus has a novel asymmetric internal structure. • The structure is largely maintained by M1-RNP cohesion within the virion. • This asymmetry plays an important role during viral entry, facilitating virus uncoating and the initiation of a productive

  8. FRET-Based Detection of M1 Muscarinic Acetylcholine Receptor Activation by Orthosteric and Allosteric Agonists

    Science.gov (United States)

    Markovic, Danijela; Holdich, Jonathan; Al-Sabah, Suleiman; Mistry, Rajendra; Krasel, Cornelius; Mahaut-Smith, Martyn P.; Challiss, R. A. John

    2012-01-01

    Background and Objective Muscarinic acetylcholine receptors (mAChRs) are 7-transmembrane, G protein-coupled receptors that regulate a variety of physiological processes and represent potentially important targets for therapeutic intervention. mAChRs can be stimulated by full and partial orthosteric and allosteric agonists, however the relative abilities of such ligands to induce conformational changes in the receptor remain unclear. To gain further insight into the actions of mAChR agonists, we have developed a fluorescently tagged M1 mAChR that reports ligand-induced conformational changes in real-time by changes in Förster resonance energy transfer (FRET). Methods Variants of CFP and YFP were inserted into the third intracellular loop and at the end of the C-terminus of the mouse M1 mAChR, respectively. The optimized FRET receptor construct (M1-cam5) was expressed stably in HEK293 cells. Results The variant CFP/YFP-receptor chimera expressed predominantly at the plasma membrane of HEK293 cells and displayed ligand-binding affinities comparable with those of the wild-type receptor. It also retained an ability to interact with Gαq/11 proteins and to stimulate phosphoinositide turnover, ERK1/2 phosphorylation and undergo agonist-dependent internalization. Addition of the full agonist methacholine caused a reversible decrease in M1 FRET (FEYFP/FECFP) that was prevented by atropine pre-addition and showed concentration-dependent amplitude and kinetics. Partial orthosteric agonists, arecoline and pilocarpine, as well as allosteric agonists, AC-42 and 77-LH-28-1, also caused atropine-sensitive decreases in the FRET signal, which were smaller in amplitude and significantly slower in onset compared to those evoked by methacholine. Conclusion The M1 FRET-based receptor chimera reports that allosteric and orthosteric agonists induce similar conformational changes in the third intracellular loop and/or C-terminus, and should prove to be a valuable molecular reagent for

  9. FRET-based detection of M1 muscarinic acetylcholine receptor activation by orthosteric and allosteric agonists.

    Directory of Open Access Journals (Sweden)

    Danijela Markovic

    Full Text Available BACKGROUND AND OBJECTIVE: Muscarinic acetylcholine receptors (mAChRs are 7-transmembrane, G protein-coupled receptors that regulate a variety of physiological processes and represent potentially important targets for therapeutic intervention. mAChRs can be stimulated by full and partial orthosteric and allosteric agonists, however the relative abilities of such ligands to induce conformational changes in the receptor remain unclear. To gain further insight into the actions of mAChR agonists, we have developed a fluorescently tagged M(1 mAChR that reports ligand-induced conformational changes in real-time by changes in Förster resonance energy transfer (FRET. METHODS: Variants of CFP and YFP were inserted into the third intracellular loop and at the end of the C-terminus of the mouse M(1 mAChR, respectively. The optimized FRET receptor construct (M(1-cam5 was expressed stably in HEK293 cells. RESULTS: The variant CFP/YFP-receptor chimera expressed predominantly at the plasma membrane of HEK293 cells and displayed ligand-binding affinities comparable with those of the wild-type receptor. It also retained an ability to interact with Gα(q/11 proteins and to stimulate phosphoinositide turnover, ERK1/2 phosphorylation and undergo agonist-dependent internalization. Addition of the full agonist methacholine caused a reversible decrease in M(1 FRET (F(EYFP/F(ECFP that was prevented by atropine pre-addition and showed concentration-dependent amplitude and kinetics. Partial orthosteric agonists, arecoline and pilocarpine, as well as allosteric agonists, AC-42 and 77-LH-28-1, also caused atropine-sensitive decreases in the FRET signal, which were smaller in amplitude and significantly slower in onset compared to those evoked by methacholine. CONCLUSION: The M(1 FRET-based receptor chimera reports that allosteric and orthosteric agonists induce similar conformational changes in the third intracellular loop and/or C-terminus, and should prove to be a

  10. Association between dwelling characteristics and concentrations of bacteria, endotoxin and fungi in settling dust

    DEFF Research Database (Denmark)

    Spilak, Michal; Knudsen, Sofie; Madsen, Anne Mette

    2014-01-01

    (Balasubramanian et al. 2012). Moisture has great influence on fungal growth and viability of bacteria. Likewise the temperature, ventilation rate and construction details reflected in the year of construction influence the moisture level in dwellings (Hägerhed-Engman, 2008; Ren et al. 2001; Bornehag et al. 2004...... to determine potential predictors that influence the presence of these microorganisms in homes. Fungi can grow on different indoor materials such as humid gypsum-boards. Fungal spores can upon exposure to airflow be aerosolised (Madsen et al. 2006). The size of the fungal spores in indoor air is usually below...... envelope (Frankel et al. 2012). Bacteria and bacterial endotoxins may enter buildings through the same pathways as fungi. However, a study of Madsen et al. (2012) has shown that concentrations of bacteria in indoor settled dust are significantly affected by presence of occupants. Endotoxins are present...

  11. Flow structures generated by elongated plates settling in a water column

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Jensen, Anna Lyhne; Hærvig, Jakob

    angle of 15° in a 0.60 m x 0.30 m  0.35 m (LBH) glass container filled with water. Continuous Particle Image Velocimetry is used to analyse both the velocity field of the continuous phase and the motion of the plates. The experiments show a well-defined oscillating motion of the plate. A stall occurs...... of the dimensionless moment of inertia and Reynolds number was investigated. The objective of the present work is to collect and present experimental data about the flow structures generated by the settling of elongated plates in a water column. The experiments are carried out by releasing the plates at an initial...... each time the plate changes horizontal direction of motion. The results show a flow building up when the plate accelerates and a vortex rolling off in each turn....

  12. JURISTIC OBSTACLE IN DECLARING BANKRUPTCY AGAINST INSURANCE COMPANY WHICH FAIL TO SETTLE ITS DEBT LIABILITY

    Directory of Open Access Journals (Sweden)

    Ali Imron

    2017-03-01

    Full Text Available Legal obligation to pay compensation of an insurance company arise immediatelyafter the evenement occurred, if this obligation not being settled right away it can becategorized as “fall due debt” and “claimable”, and this can be used as a reason to proposebankruptcy application. The creditor’s fundamental rights practically impeded by Section 2article (5 of Insolvency Act, which give absolute authority to Minister of Finance in proposingbankruptcy application for insurance company. This authority is attached to the status of Ministerof Finance as the guider and supervisor of insurance institution in Indonesia, but this authorityoften might reduce people’s trust to insurance institution itself if it is not used carefully andwisely. For the sake of law and justice, Minister of Finance should acts proportionally if thebankruptcy application doesn’t have enough reason, according to Minister’s authority in thecase of bankruptcy application for insurance company against their insured and other creditors.

  13. The solar continuum intensity distribution: Settling the conflict between observations and simulations

    CERN Document Server

    Wedemeyer-Böhm, S

    2009-01-01

    For many years, there seemed to be significant differences between the continuum intensity distributions derived from observations and simulations of the solar photosphere. In order to settle the discussion on these apparent discrepancies, we present a detailed comparison between simulations and seeing-free observations that takes into account the crucial influence of instrumental image degradation. We use a set of images of quiet Sun granulation taken in the blue, green and red continuum bands of the Broadband Filter Imager of the Solar Optical Telescope (SOT) onboard Hinode. The images are deconvolved with Point Spread Functions (PSF) that account for non-ideal contributions due to instrumental stray-light and imperfections. In addition, synthetic intensity images are degraded with the corresponding PSFs. The results are compared with respect to spatial power spectra, intensity histograms, and the centre-to-limb variation of the intensity contrast. The observational findings are well matched with correspond...

  14. Critical yield numbers of rigid particles settling in Bingham fluids and Cheeger sets

    CERN Document Server

    Frigaard, Ian A; Mercier, Gwenael; Pöschl, Christiane; Scherzer, Otmar

    2016-01-01

    We consider the fluid mechanical problem of identifying the critical yield number $Y_c$ of a dense solid inclusion (particle) settling under gravity within a bounded domain of Bingham fluid, i.e. the critical ratio of yield stress to buoyancy stress that is sufficient to prevent motion. We restrict ourselves to a two-dimensional planar configuration with a single anti-plane component of velocity. Thus, both particle and fluid domains are infinite cylinders of fixed cross-section. We show that such yield numbers arise from an eigenvalue problem for a constrained total variation. We construct particular solutions to this problem by consecutively solving two Cheeger-type set optimization problems. We present a number of example geometries in which these geometric solutions can be found explicitly and discuss general features of the solutions. Finally, we consider a computational method for the eigenvalue problem, which is seen in numerical experiments to produce these geometric solutions.

  15. Dynamic one-dimensional modeling of secondary settling tanks and system robustness evaluation.

    Science.gov (United States)

    Li, Ben; Stenstrom, M K

    2014-01-01

    One-dimensional secondary settling tank models are widely used in current engineering practice for design and optimization, and usually can be expressed as a nonlinear hyperbolic or nonlinear strongly degenerate parabolic partial differential equation (PDE). Reliable numerical methods are needed to produce approximate solutions that converge to the exact analytical solutions. In this study, we introduced a reliable numerical technique, the Yee-Roe-Davis (YRD) method as the governing PDE solver, and compared its reliability with the prevalent Stenstrom-Vitasovic-Takács (SVT) method by assessing their simulation results at various operating conditions. The YRD method also produced a similar solution to the previously developed Method G and Enquist-Osher method. The YRD and SVT methods were also used for a time-to-failure evaluation, and the results show that the choice of numerical method can greatly impact the solution. Reliable numerical methods, such as the YRD method, are strongly recommended.

  16. SEMICONDUCTOR INTEGRATED CIRCUITS: A low power fast-settling frequency-presetting PLL frequency synthesizer

    Science.gov (United States)

    Zhiqing, Geng; Xiaozhou, Yan; Wenfeng, Lou; Peng, Feng; Nanjian, Wu

    2010-08-01

    This work presents the design and implementation of a 2.4 GHz low power fast-settling frequency-presetting PLL frequency synthesizer in the 0.18 μm CMOS process. A low power mixed-signal LC VCO, a low power dual mode prescaler and a digital processor with non-volatile memory are developed to greatly reduce the power consumption and the setting time. The digital processor can automatically calibrate the presetting frequency and accurately preset the frequency of the VCO under process variations. The experimental results demonstrate that the power consumption of the synthesizer is about 4 mA @ 1.8 V and that the typical setting time of the synthesizer is less than 3 μs.

  17. Spin, slip, and settle: effects of shape on motion for Taylor-scale particles in homogeneous isotropic turbulence

    Science.gov (United States)

    Byron, Margaret; Tao, Yiheng; Houghton, Isabel; Variano, Evan

    2014-11-01

    We fabricate hydrogel cylinders of varying aspect ratios and suspend them in homogeneous isotropic turbulence at high Reynolds number. Cylinders are nearly neutrally buoyant and refractive-index-matched to water, with characteristic lengthscales that are close to the Taylor microscale. We simultaneously image these cylinders and the surrounding fluid for stereoscopic PIV measurement, permitting calculation of instantaneous particle slip velocity. We measure the particles' settling velocity in quiescent flow and compare this to both the calculated slip velocities and empirically-predicted settling velocities. Particle rotation is determined via the solid-body rotation equation and compared with fluid-phase properties (vorticity, shear, et al). We find that the aspect ratio of the cylinder has only a weak effect on its expected value of angular velocity magnitude, and further examine the influence of aspect ratio on slip and settling velocities. Lastly, we discuss applications of our results to problems of underwater navigation in aquatic organisms.

  18. A fast-settling frequency-presetting PLL frequency synthesizer with process variation compensation and spur reduction

    Science.gov (United States)

    Xiaozhou, Yan; Xiaofei, Kuang; Nanjian, Wu

    2009-04-01

    This paper proposes a fast-settling frequency-presetting PLL frequency synthesizer. A mixed-signal VCO and a digital processor are developed to accurately preset the frequency of VCO and greatly reduce the settling time. An auxiliary tuning loop is introduced in order to reduce reference spur caused by leakage current. The digital processor can automatically compensate presetting frequency variation with process and temperature, and control the operation of the auxiliary tuning loop. A 1.2 GHz integer-N synthesizer with 1 MHz reference input was implemented in a 0.18 μm process. The measured results demonstrate that the typical settling time of the synthesizer is less than 3 μs, and the phase noise is -108 dBc/Hz@ 1MHz. The reference spur is -52 dBc.

  19. A fast-settling frequency-presetting PLL frequency synthesizer with process variation compensation and spur reduction

    Institute of Scientific and Technical Information of China (English)

    Yan Xiaozhou; Kuang Xiaofei; Wu Nanjian

    2009-01-01

    This paper proposes a fast-settling frequency-presetting PLL frequency synthesizer.A mixed-signal VCO and a digital processor are developed to accurately preset the frequency of VCO and greatly reduce the settling time.An auxiliary tuning loop is introduced in order to reduce reference spur caused by leakage current.The digital processor can automatically compensate presetting frequency variation with process and temperature,and control the operation of the auxiliary tuning loop.A 1.2 GHz integer-N synthesizer with 1 MHz reference input Was implemented in a 0.18μm process.The measured results demonstrate that the typical settling time of the synthesizer is less than 3μs,and the phase noise is-108 dBc/Hz@1MHz.The reference spur is-52 dBc.

  20. Significance of uncertainties derived from settling tank model structure and parameters on predicting WWTP performance - A global sensitivity analysis study

    DEFF Research Database (Denmark)

    Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen

    2011-01-01

    Uncertainty derived from one of the process models – such as one-dimensional secondary settling tank (SST) models – can impact the output of the other process models, e.g., biokinetic (ASM1), as well as the integrated wastewater treatment plant (WWTP) models. The model structure and parameter...... uncertainty of settler models can therefore propagate, and add to the uncertainties in prediction of any plant performance criteria. Here we present an assessment of the relative significance of secondary settling model performance in WWTP simulations. We perform a global sensitivity analysis (GSA) based....... The outcome of this study contributes to a better understanding of uncertainty in WWTPs, and explicitly demonstrates the significance of secondary settling processes that are crucial elements of model prediction under dry and wet-weather loading conditions....

  1. New probe of M1 and E1 strengths in GDR regions

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, T. [Japan Atomic Energy Agency and National Astronomical Observatory in Japan (Japan); Ogata, K. [RCNP, Osaka University (Japan); Miyamoto, S.; Mochizuki, T.; Horikawa, K.; Amano, S. [University of Hyogo (Japan); Imazaki, K.; Li, D.; Izawa, Y. [Institute for Laser Technology (Japan); Chiba, S. [Tokyo Institute of Technology (Japan)

    2014-05-02

    The M1 strengths (or level density of 1{sup +} states) are of importance for estimation of interaction strengths between neutrinos and nuclei for the study of the supernova neutrino-process. In 1957, Agodi predicted theoretically angular distribution of neutrons emitted from states excited via dipole transitions with linearly polarized gamma-ray beam at the polar angle of θ=90° should be followed by a simple function, a + b cos(2φ), where φ, is azimuthal angel. However, this theoretical prediction has not been verified over the wide mass region except for light nuclei as deuteron. We have measured neutron angular distributions with (polarized gamma, n) reactions on Au, Nal, and Cu. We have verified the Agodi's prediction for the first time over the wide mass region. This suggests that (polarized gamma, n) reactions may be useful tools to study M1 strengths in giant resonance regions.

  2. Design and optimization of selective azaindole amide M1 positive allosteric modulators.

    Science.gov (United States)

    Davoren, Jennifer E; O'Neil, Steven V; Anderson, Dennis P; Brodney, Michael A; Chenard, Lois; Dlugolenski, Keith; Edgerton, Jeremy R; Green, Michael; Garnsey, Michelle; Grimwood, Sarah; Harris, Anthony R; Kauffman, Gregory W; LaChapelle, Erik; Lazzaro, John T; Lee, Che-Wah; Lotarski, Susan M; Nason, Deane M; Obach, R Scott; Reinhart, Veronica; Salomon-Ferrer, Romelia; Steyn, Stefanus J; Webb, Damien; Yan, Jiangli; Zhang, Lei

    2016-01-15

    Selective activation of the M1 receptor via a positive allosteric modulator (PAM) is a new approach for the treatment of the cognitive impairments associated with schizophrenia and Alzheimer's disease. A novel series of azaindole amides and their key pharmacophore elements are described. The nitrogen of the azaindole core is a key design element as it forms an intramolecular hydrogen bond with the amide N-H thus reinforcing the bioactive conformation predicted by published SAR and our homology model. Representative compound 25 is a potent and selective M1 PAM that has well aligned physicochemical properties, adequate brain penetration and pharmacokinetic (PK) properties, and is active in vivo. These favorable properties indicate that this series possesses suitable qualities for further development and studies.

  3. IKKα Promotes Intestinal Tumorigenesis by Limiting Recruitment of M1-like Polarized Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Serkan I. Göktuna

    2014-06-01

    Full Text Available The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC therapy.

  4. Extended M1 sum rule for excited symmetric and mixed-symmetry states in nuclei

    CERN Document Server

    Smirnova, N A; Leviatan, A; Ginocchio, J N; Fransen, C

    2002-01-01

    A generalized M1 sum rule for orbital magnetic dipole strength from excited symmetric states to mixed-symmetry states is considered within the proton-neutron interacting boson model of even-even nuclei. Analytic expressions for the dominant terms in the B(M1) transition rates from the first and second $2^+$ states are derived in the U(5) and SO(6) dynamic symmetry limits of the model, and the applicability of a sum rule approach is examined at and in-between these limits. Lastly, the sum rule is applied to the new data on mixed-symmetry states of 94Mo and a quadrupole d-boson ratio $nd(0^+_1)/nd(2^+_2) \\approx 0.6$ is obtained in a largely parameter-independent way

  5. M=1 and 2 gravitational instabilities in gaseous disks; 1, diffuse gas

    CERN Document Server

    Junqueira, S

    1996-01-01

    We report the results of self-gravitating simulations of spiral galaxies, modeled by stellar and gaseous components, developed to investigate in particular the role of dissipation in the evolution of galaxy disks. The gas disk is simulated by the Beam-Scheme method, where it is considered as a self-gravitating fluid. The results suggest that the gravitational coupling between the stars and gas plays a fundamental role in the formation and dissolution of stellar bars, depending on the gaseous mass concentration and on the degree of dissipation. In addition we remark that initially concentrated gas disks can be unstable to the one-armed (m=1) spiral perturbations, which may explain the lopsided features observed in the gas distribution of the late-type isolated galaxies. The development of the m=1 feature slows down the radial gas flows towards the center, since the large-scale gravity torques are then much weaker.

  6. Cholinergic impact on neuroplasticity drives muscarinic M1 receptor mediated differentiation into neurons.

    Science.gov (United States)

    Benninghoff, Jens; Rauh, Werner; Brantl, Victor; Schloesser, Robert J; Moessner, Rainald; Möller, Hans-Jürgen; Rujescu, Dan

    2013-04-01

    Increasing evidence indicates that canonical neurotransmitters act as regulatory signals during neuroplasticity. Here, we report that muscarinic cholinergic neurotransmission stimulates differentiation of adult neural stem cells in vitro. Adult neural stem cells (ANSC) dissociated from the adult mouse hippocampus were expanded in culture with basic fibroblast growth factor (BFGF) and epidermal growth factor (EGF). Carbachol (CCh), an analog of acetylcholine (ACh) significantly enhanced de novo differentiation into neurons on bFGF- and EGF-deprived stem cells as shown by the percentage of TUJ1 positive cells. By contrast, pirenzepine (PIR), a muscarinic M1 receptor antagonist, reduced the generation of neurons. Activation of cholinergic signaling drives the de novo differentiation of uncommitted stem cells into neurons. These effects appear to be predominantly mediated via the muscarinic M1 receptor subtype.

  7. Commercial scale demonstration enhanced oil recovery by miceller-polymer flooding. M-1 project: facilities report

    Energy Technology Data Exchange (ETDEWEB)

    Knight, B.L. (ed.)

    1977-04-01

    ERDA and Marathon Oil Company contracted together for a commercial scale demonstration of enhanced oil recovery by the Maraflood (TM) oil recovery process. This M-1 Project is located within Sections 15, 16, 21 and 22, T6N, R13W, Crawford County, Illinois, encompassing approximately 407 acres of Robinson Sand reservoir developed in the first decade of the century. The area covers portions of several waterfloods developed on 10-acre spacing in the 1950's that were approaching their economic limit. This report describes all M-1 Project facilities, how they were prepared or constructed, their purpose and how they operate: (1) wells (drilling and completion); (2) production facility; (3) injection facility; and (4) various service systems required during project development and/or operation. (48 fig, 7 tables) (DLC).

  8. Data on sulforaphane treatment mediated suppression of autoreactive, inflammatory M1 macrophages

    Directory of Open Access Journals (Sweden)

    Sanjima Pal

    2016-06-01

    Full Text Available Any chronic, inflammatory, autoimmune disease (e.g. arthritis associated pathogenesis directs uncontrolled accumulation of both soluble forms of collagens in the synovial fluids and M1 macrophages around inflamed tissues. Despite of few studies demonstrating efficiency of Sulforaphane (SFN in suppressing arthritis associated collagen restricted T cells or fibroblasts, its effects on macrophage polarity and plasticity are less understood. Recently, we reported regulation of phenotypic and functional switching by SFN in induced and spontaneously differentiating human monocytes [1]. Here, flow cytometry, western blot and ELISA derived data demonstrated that SFN inhibited in vitro inflammatory responses developed by soluble human collagens (I–IV induced auto-reactive M1 type monocyte/macrophage model.

  9. THE BULK INPUT M[X]/M/1 QUEUE WITH WORKING VACATIONS

    Institute of Scientific and Technical Information of China (English)

    Xiuli XU; Mingxin LIU; Xiaohua ZHAO

    2009-01-01

    In this paper, we analyze a bulk input M[X]/M/1 queue with multiple working vacations. A quasi upper triangle transition probability matrix of two-dimensional Markov chain in this model is obtained, and with the matrix analysis method, highly complicated probability generating function(PGF) of the stationary queue length is firstly derived, from which we got the stochastic decomposition result for the stationary queue length which indicates the evident relationship with that of the classical M[X]/M/1 queue without vacation. It is important that we find the upper and the lower bounds of the stationary waiting time in the Laplace transform order using the properties of the conditional Erlang distribution. Furthermore, we gain the mean queue length and the upper and the lower bounds of the mean waiting time.

  10. Formation of Polyhydroxyalkanoate Blends by Pseudomonas pseudoalcaligenes M1-2 from Various Carbon Sources

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Pseudomonas pseudoalcaligenes strain M1-2 isolated from oil-contaminated soil collected from an oilfield in northern China was found to be able to synthesize a blend of polyhydroxyalkanoates (PHAs) containing monomers of 3-hydroxybutyrate (C4), 3-hydroxyvalerate (C5), 3-hydroxyheptanoate (C7), 3-hydroxyoctanoate (C8), 3-hydroxynonanoate (C9), 3-hydroxydecanoate (C10) and 3-hydroxydodecanoate (C12) from various carbon sources.The hydroxyalkanoate (HA) monomer composition varied both quantitatively and qualitatively, depending on the carbon sources used.The presence of octanoate in substrates of myristic acid or tridecanoate promoted the synthesis of HB monomer in the blend.Concentration of octanoate was also found to significantly affect the PHB content in the blend.A PHA biosynthesis pathway in Pseudomonas pseudoalcaligens M1-2 was proposed.

  11. Acylsucrose-producing tomato plants forces Bemisia tabaci to shift its preferred settling and feeding site.

    Directory of Open Access Journals (Sweden)

    Maria Jose Rodríguez-López

    Full Text Available BACKGROUND: The whitefly Bemisia tabaci (Genn. causes dramatic damage to plants by transmitting yield-limiting virus diseases. Previous studies proved that the tomato breeding line ABL 14-8 was resistant to B. tabaci, the vector of tomato yellow leaf curl disease (TYLCD. This resistance is based on the presence of type IV glandular trichomes and acylsucrose production. These trichomes deter settling and probing of B. tabaci in ABL 14-8, which reduces primary and secondary spread of TYLCD. METHODOLOGY/PRINCIPAL FINDINGS: Whitefly settlement preference was evaluated on the adaxial and abaxial leaf surfaces of nearly-isogenic tomato lines with and without B. tabaci-resistance traits, 'ABL 14-8 and Moneymaker' respectively, under non-choice and free-choice conditions. In addition, the Electrical Penetration Graph technique was used to study probing and feeding activities of B. tabaci on the adaxial and abaxial leaf surfaces of the same genotypes. B. tabaci preferred to settle on the abaxial than on the adaxial surface of 'Moneymaker' leaves, whereas no such preference was observed on ABL 14-8 tomato plants at the ten-leaf growth stage. Furthermore, B. tabaci preferred to feed on the abaxial than on the adaxial leaf surface of 'Moneymarker' susceptible tomato plants as shown by a higher number of sustained phloem feeding ingestion events and a shorter time to reach the phloem. However, B. tabaci standard probing and feeding behavior patterns were altered in ABL 14-8 plants and whiteflies were unable to feed from the phloem and spent more time in non-probing activities when exposed to the abaxial leaf surface. CONCLUSIONS/SIGNIFICANCE: The distorted behavior of B. tabaci on ABL 14-8 protects tomato plants from the transmission of phloem-restricted viruses such as Tomato yellow leaf curl virus (TYLCV, and forces whiteflies to feed on the adaxial side of leaves where they feed less efficiently and become more vulnerable to natural enemies.

  12. Polycyclic aromatic hydrocarbons (PAHs) in the settled dust of automobile workshops, health and carcinogenic risk evaluation.

    Science.gov (United States)

    Ali, Nadeem; Ismail, Iqbal Mohammad Ibrahim; Khoder, Mamdouh; Shamy, Magdy; Alghamdi, Mansour; Al Khalaf, Abdulrahman; Costa, Max

    2017-12-01

    There are studies available on the occurrence of PAHs in indoor settled dust from residential and different occupational settings in literature but limited data is available on their occurrence and potential health risk assessment in automobile workshops. In recent decades Saudi Arabia has experienced tremendous growth in the petroleum industry and as a result, the automobile industry is booming. People working in automobile workshops are at a greater risk of exposure to chemicals releasing from the petroleum products. The main objective of this study was to report PAHs in settled dust from different automobile workshops of Jeddah, Saudi Arabia, and evaluate health risk for workers through dust exposure. Pyrene (1585-13500ng/g), Benz[a]anthracene (risk assessment was calculated based on benzo[a]pyrene equivalent carcinogenic power (BaPE), incremental lifetime cancer risk (ILCR), and daily exposure to PAHs via dust ingestion. The median concentration of BaPE was 285ng/g, ILCR was up to 6.78×10(-3) (exceeded reference values of USEPA (range between 1×10(-6) and 1×10(-4))), and worker's exposure via dust ingestion on daily bases reached up to 33ng/kgbw/day for ∑12PAHs. This study showed people working in automobile workshops in the studied area are getting expose to high levels of PAHs via dust ingestion, inhalation, and dermal contact. This is the first study reporting PAHs in automobile workshops settings from Middle East. The incremental lifetime cancer risk to workers via dust exposure exceeded set limits of USEPA. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Bulking sludge for PHA production: Energy saving and comparative storage capacity with well-settled sludge

    Institute of Scientific and Technical Information of China (English)

    Qinxue Wen; Zhiqiang Chen; Changyong Wang; Nanqi Ren

    2012-01-01

    Two acetate-fed sequencing batch reactors (SBR) were operated under an aerobic dynamic feeding (ADF) model (SBR#2) and with anaerobic phase before aerobic phase (SBR#1) to select mixed cultures with a high polyhydroxyalkanoates (PHA) storage response.Although kinetic selection based on storage response should bring about a predominance of floc-formers,a bulking sludge with storage response comparable to well-settled sludge was steadily established.An anaerobic phase was introduced before the aerobic phase in the ADF model to improve the sludge settleability (SBR #1),however,due to the consequent increased feast/famine ratio,the performance of SBR #1,in terms of both the maximum PHB (polyhydroxybutyrate) cell content and △PHB,was lower than that of SBR #2.SBR #2 gradually reached a steady state while SBR #1 failed suddenly after 50 days of operation.The maximum specific substrate uptake rate and storage rate for the selected bulking sludge were 0.4 Cmol Ac/(Cmol X.hr) and 0.18 Cmol Ac/(Cmol PHB.hr),respectively,resulting a yield of 0.45 Cmol PHB/(Cmol Ac) in SBR #2 in the culture enrichment phase.A maximum PHB content of 53% of total suspended solids and PHB storage rate of 1.36 Cmol Ac/(Cmol PHB.hr) was achieved at 10.2 hr in batch accumulation tests under nitrogen starvation.The results indicated that it was feasible to utilize filamentous bacteria to accumulate PHA with a rate comparable to well-settled sludge.Furthermore,the lower dissolved oxygen demand of filamentous bacteria would save energy required for aeration in the culture enrichment stage.

  14. Instantaneous Flow Structures and Opportunities for Larval Settlement: Barnacle Larvae Swim to Settle.

    Directory of Open Access Journals (Sweden)

    Ann I Larsson

    Full Text Available Water flow affects settlement of marine larvae on several scales. At the smallest scale local flow regime may control the probability of adhesion to the substrate. Our aim was to mechanistically understand the transition from suspended to attached larvae in turbulent flow. Recently it was proposed that opportunities for larval settlement in turbulent boundary layers depend on time windows with suitable instantaneous flow properties. In flume flow we characterized the proportion of suitable time windows in a series of flow velocities with focus on the near-bed flow. The change in the proportion of potential settling windows with increasing free-stream velocities was compared to the proportion of temporary attachment of barnacle cypris larvae at different flow velocities. We found large instantaneous flow variations in the near-bed flow where cyprid attachment took place. The probability of temporary attachment in cyprids declined with local flow speed and this response was compatible with a settling window lasting at least 0.1 s with a maximum local flow speed of 1.9-2.4 cm s-1. Cyprids swam against the near-bed flow (negative rheotaxis and the swimming speed (1.8 cm s-1 was close to the critical speed that permitted temporary attachment. We conclude that temporary attachment in barnacle cyprids requires upstream swimming to maintain a fixed position relative to the substrate for at least 0.1 s. This behaviour may explain the ability of barnacles to recruit to high-flow environments and give cyprids flexibility in the pre-settlement choice of substrates based on flow regime.

  15. Impacts of sediments on coral energetics: partitioning the effects of turbidity and settling particles.

    Directory of Open Access Journals (Sweden)

    Reef K Junjie

    Full Text Available Sediment loads have long been known to be deleterious to corals, but the effects of turbidity and settling particles have not previously been partitioned. This study provides a novel approach using inert silicon carbide powder to partition and quantify the mechanical effects of sediment settling versus reduced light under a chronically high sedimentary regime on two turbid water corals commonly found in Singapore (Galaxea fascicularis and Goniopora somaliensis. Coral fragments were evenly distributed among three treatments: an open control (30% ambient PAR, a shaded control (15% ambient PAR and sediment treatment (15% ambient PAR; 26.4 mg cm(-2 day(-1. The rate of photosynthesis and respiration, and the dark-adapted quantum yield were measured once a week for four weeks. By week four, the photosynthesis to respiration ratio (P/R ratio and the photosynthetic yield (Fv/Fm had fallen by 14% and 3-17% respectively in the shaded control, contrasting with corals exposed to sediments whose P/R ratio and yield had declined by 21% and 18-34% respectively. The differences in rates between the shaded control and the sediment treatment were attributed to the mechanical effects of sediment deposition. The physiological response to sediment stress differed between species with G. fascicularis experiencing a greater decline in the net photosynthetic yield (13% than G. somaliensis (9.5%, but a smaller increase in the respiration rates (G. fascicularis = 9.9%, G. somaliensis  = 14.2%. These different physiological responses were attributed, in part, to coral morphology and highlighted key physiological processes that drive species distribution along high to low turbidity and depositional gradients.

  16. Modulating activity of M1 receptor to the reaction of ileal smooth muscle.

    Science.gov (United States)

    Glaza, Izabela; Szadujkis-Szadurski, Leszek; Szadujkis-Szadurski, Rafał; Gajdus, Marta; Olkowska, Joanna

    2011-08-03

    The subject of the study was determination of the effect of drugs on ileal smooth muscle contraction induced by activation of M(1) type muscarinic receptors. Drugs that have an effect on muscarinic receptors are divided to agonists, with close ties to the receptor and high internal activity and antagonists, with no internal activity. Conducted experiments tested interactions between a broad-spectrum agonist of muscarinic receptors, carbachol and a selective muscarinic receptor antagonist of M(1) type, pirenzepine. Testing was conducted on tissues isolated from rat's intestine. Male Wistar rats with weight between 220 g and 360 g were anesthetized by intraperitoneal injection of urethane (120 mg/kg). Concentration-effect curves were determined with the use of cumulated concentration method, in accordance with the van Rossum method (1963) in Kenakin modification (2006). The purpose of the study was determination of concentration-effect curves for carbachol. This curve was compared with the curve of receptor occupation depending on concentration of this drug. Based on concentration-effect curves, the average value of EC(50) was calculated for carbachol, amounting to 2.44×10(-6) [M/l]. The results confirmed that atropine is effective in stopping contractions caused by carbachol, meeting the conditions of competitive antagonists. Atropine caused the shift of curves for carbachol to the right. Pirenzepine, selectively blocking muscarinic receptors of M(1) type gave similar results. It was proved that in the preparation of gastric fundus smooth muscle, M(1) type receptors occur not only presynaptically, but also postsynaptically.

  17. Modulating activity of M1 receptor to the reaction of ileal smooth muscle

    Directory of Open Access Journals (Sweden)

    Izabela Glaza

    2011-08-01

    Full Text Available Background:The subject of the study was determination of the effect of drugs on ileal smooth muscle contraction induced by activation of M1 type muscarinic receptors. Drugs that have an effect on muscarinic receptors are divided to agonists, with close ties to the receptor and high internal activity and antagonists, with no internal activity. Conducted experiments tested interactions between a broad-spectrum agonist of muscarinic receptors, carbachol and a selective muscarinic receptor antagonist of M1 type, pirenzepine.Material/Methods:Testing was conducted on tissues isolated from rat’s intestine. Male Wistar rats with weight between 220 g and 360 g were anesthetized by intraperitoneal injection of urethane (120 mg/kg. Concentration-effect curves were determined with the use of cumulated concentration method, in accordance with the van Rossum method (1963 in Kenakin modification (2006.Results:The purpose of the study was determination of concentration-effect curves for carbachol. This curve was compared with the curve of receptor occupation depending on concentration of this drug. Based on concentration-effect curves, the average value of EC50 was calculated for carbachol, amounting to 2.44×10–6 [M/l].Conclusions:The results confirmed that atropine is effective in stopping contractions caused by carbachol, meeting the conditions of competitive antagonists. Atropine caused the shift of curves for carbachol to the right. Pirenzepine, selectively blocking muscarinic receptors of M1 type gave similar results. It was proved that in the preparation of gastric fundus smooth muscle, M1 type receptors occur not only presynaptically, but also postsynaptically.

  18. Role of M1 receptor in regulation of gastric fundus smooth muscle contraction

    Directory of Open Access Journals (Sweden)

    Marta Gajdus

    2011-09-01

    Full Text Available Background:The subject of this study is determination of the influence of drugs on gastric fundus smooth muscle contraction induced by activation of muscarinic receptors M1. Experiments tested interactions between a receptor agonist, carbachol and muscarinic receptor antagonists, atropine and pirenzepine.Material/Methods:Testing was conducted on tissues isolated from rat’s stomach. Male Wistar rats with weight between 220 g and 360 g were anesthetized by intraperitoneal injection of urethane (120 mg/kg. The stomach was dissected, and later the gastric fundus was isolated. Tissue was placed in a dish for insulated organs with 20 ml in capacity, filled with Krebs fluid. Results contained in the study are average values ± SE. In order to determine statistical significance, the principles of receptor theory were used (Kenakin modification.Results:According to tests, carbachol, in concentrations ranging between 10–8 M to 10–4 M, in a dosage-dependent way induces gastric fundus smooth muscle contraction. Presented results indicate that carbachol meets the conditions posed to full agonists. On the other hand, atropine, a non-selective muscarinic receptor antagonist, causes a concentration-dependent shift of concentration-effect curve (for carbachol to the right, maintaining maximum reaction. According to analysis of the curve determined, we can deduce that atropine meets the conditions posed to competitive antagonists. The use of pirenzepine, a competitive receptor agonist M1, causes shift of concentration-effect curve (for carbachol to the right, maintaining maximum reaction.Conclusions:From the testing conducted on the preparation of the gastric fundus we can deduce that atropine causes shift of concentration-effect curves for carbachol to the right. A similar effect is released by pirenzepine, selectively blocking muscarinic receptors of M1 type. The results indicate that in the preparation of the gastric fundus smooth muscle, M1 type

  19. Role of M1 receptor in regulation of gastric fundus smooth muscle contraction.

    Science.gov (United States)

    Gajdus, Marta; Szadujkis-Szadurska, Katarzyna; Szadujkis-Szadurski, Leszek; Glaza, Izabela; Szadujkis-Szadurski, Rafał; Olkowska, Joanna

    2011-09-14

    The subject of this study is determination of the influence of drugs on gastric fundus smooth muscle contraction induced by activation of muscarinic receptors M1. Experiments tested interactions between a receptor agonist, carbachol and muscarinic receptor antagonists, atropine and pirenzepine. Testing was conducted on tissues isolated from rat's stomach. Male Wistar rats with weight between 220 g and 360 g were anesthetized by intraperitoneal injection of urethane (120 mg/kg). The stomach was dissected, and later the gastric fundus was isolated. Tissue was placed in a dish for insulated organs with 20 ml in capacity, filled with Krebs fluid. Results contained in the study are average values ± SE. In order to determine statistical significance, the principles of receptor theory were used (Kenakin modification). According to tests, carbachol, in concentrations ranging between 10(-8) M to 10(-4) M, in a dosage-dependent way induces gastric fundus smooth muscle contraction. Presented results indicate that carbachol meets the conditions posed to full agonists. On the other hand, atropine, a non-selective muscarinic receptor antagonist, causes a concentration-dependent shift of concentration-effect curve (for carbachol) to the right, maintaining maximum reaction. According to analysis of the curve determined, we can deduce that atropine meets the conditions posed to competitive antagonists. The use of pirenzepine, a competitive receptor agonist M1, causes shift of concentration-effect curve (for carbachol) to the right, maintaining maximum reaction. From the testing conducted on the preparation of the gastric fundus we can deduce that atropine causes shift of concentration-effect curves for carbachol to the right. A similar effect is released by pirenzepine, selectively blocking muscarinic receptors of M1 type. The results indicate that in the preparation of the gastric fundus smooth muscle, M1 type receptors occur also postsynaptically.

  20. "5M1E"法在生产管理中的运用

    Institute of Scientific and Technical Information of China (English)

    刘秋香

    2010-01-01

    人(man)、机械(machine)、材料(material)、方法(method)、环境(enviroment)、管理(manage)这几个主要环节实行全面质量管理,称为"5M1E"法.在生产管理中应用该法,可以达到提升人品质、提升产品品质,提高员工士气.

  1. Radiationless transitions to atomic M 1,2,3 shells - Results of relativistic theory

    Science.gov (United States)

    Chen, M. H.; Crasemann, B.; Mark, H.

    1983-01-01

    Radiationless transitions filling vacancies in atomic M1, M2, and M3 subshells have been calculated relativistically with Dirac-Hartree-Slater wave functions for ten elements with atomic numbers 67-95. Results are compared with those of nonrelativistic calculations and experiment. Relativistic effects are found to be significant. Limitations of an independent-particle model for the calculation of Coster-Kronig rates are noted.

  2. Study of Mutagenic Effects of M1 Generation of Maize Seeds Irradiated by Heavy Ions

    Institute of Scientific and Technical Information of China (English)

    LUOHong-bing; ZHAOKui; GUOJi-yu; SUILi; NIMei-nan; MEIJun-ping; LUXiu-qin; ZHOUPing; KONGFu-quan; ZHANGGen-fa

    2003-01-01

    In order to study M1 biological effects induced by heavy ion irradiation on maize seeds, the embryos of dry maize seeds are irradiated with 7Li and 12C ions. The experiment is performed at the heavy ion scanning tube of the HI-13 tandem accelerator. The beam goes through a thickness of 25μm. Then the maize seeds are irradiated in the air uniformly.

  3. Cellular stress response in human Müller cells (MIO-M1) after bevacizumab treatment.

    Science.gov (United States)

    Matsuda, Monique; Krempel, Paloma Gava; Marquezini, Mônica Valeria; Sholl-Franco, Alfred; Lameu, Amanda; Monteiro, Mário Luiz R; Miguel, Nádia Campos de Oliveira

    2017-07-01

    Bevacizumab, an anti-vascular endothelial growth factor (VEGF) agent, is widely used in the treatment of retinal vascular diseases. However, due to the essential role Müller cell derived-VEGF plays in the maintenance of retinal neurons and glial cells, cell viability is likely to be affected by VEGF inhibition. We therefore evaluated the effect of bevacizumab-induced VEGF inhibition on Müller cells (MIO-M1) in vitro. MIO-M1 cells were cultured for 12 or 24 h in media containing bevacizumab at 0.25 or 0.5 mg/mL. Controls were cultured in medium only. Cell viability was determined with the trypan blue exclusion test and MTT assay. Caspase-3, beclin-1, glial fibrillary acidic protein (GFAP) and vimentin content were quantified by immunohistochemistry. Gene expression was evaluated by real-time quantitative PCR. Treatment with bevacizumab did not reduce MIO-M1 cell viability, but increased metabolic activity at 24 h (0.5 mg/mL) and induced apoptosis and autophagy, as shown by the increased caspase-3 levels at 12 h (0.25 and 0.5 mg/mL) and the increased beclin levels at 24 h (0.5 mg/mL). Caspase-3 mRNA was upregulated at 12 h and downregulated at 24 h in cells treated with bevacizumab at 0.25 mg/mL. Bevacizumab treatment was also associated with structural protein abnormalities, with decreased GFAP and vimentin content and upregulated GFAP and vimentin mRNA expression. Although bevacizumab did not significantly affect MIO-M1 cell viability, it led to metabolic and molecular changes (apoptosis, autophagy and structural abnormalities) suggestive of significant cellular toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Fingerprinting the substrate specificity of M1 and M17 aminopeptidases of human malaria, Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Marcin Poreba

    Full Text Available BACKGROUND: Plasmodium falciparum, the causative agent of human malaria, expresses two aminopeptidases, PfM1AAP and PfM17LAP, critical to generating a free amino acid pool used by the intraerythrocytic stage of the parasite for proteins synthesis, growth and development. These exopeptidases are potential targets for the development of a new class of anti-malaria drugs. METHODOLOGY/PRINCIPAL FINDINGS: To define the substrate specificity of recombinant forms of these two malaria aminopeptidases we used a new library consisting of 61 fluorogenic substrates derived both from natural and unnatural amino acids. We obtained a detailed substrate fingerprint for recombinant forms of the enzymes revealing that PfM1AAP exhibits a very broad substrate tolerance, capable of efficiently hydrolyzing neutral and basic amino acids, while PfM17LAP has narrower substrate specificity and preferentially cleaves bulky, hydrophobic amino acids. The substrate library was also exploited to profile the activity of the native aminopeptidases in soluble cell lysates of P. falciparum malaria. CONCLUSIONS/SIGNIFICANCE: This data showed that PfM1AAP and PfM17LAP are responsible for majority of the aminopeptidase activity in these extracts. These studies provide specific substrate and mechanistic information important for understanding the function of these aminopeptidases and could be exploited in the design of new inhibitors to specifically target these for anti-malaria treatment.

  5. Fingerprinting the Substrate Specificity of M1 and M17 Aminopeptidases of Human Malaria, Plasmodium falciparum

    Science.gov (United States)

    Poreba, Marcin; McGowan, Sheena; Skinner-Adams, Tina S.; Trenholme, Katharine R.; Gardiner, Donald L.; Whisstock, James C.; To, Joyce; Salvesen, Guy S.; Dalton, John P.; Drag, Marcin

    2012-01-01

    Background Plasmodium falciparum, the causative agent of human malaria, expresses two aminopeptidases, PfM1AAP and PfM17LAP, critical to generating a free amino acid pool used by the intraerythrocytic stage of the parasite for proteins synthesis, growth and development. These exopeptidases are potential targets for the development of a new class of anti-malaria drugs. Methodology/Principal Findings To define the substrate specificity of recombinant forms of these two malaria aminopeptidases we used a new library consisting of 61 fluorogenic substrates derived both from natural and unnatural amino acids. We obtained a detailed substrate fingerprint for recombinant forms of the enzymes revealing that PfM1AAP exhibits a very broad substrate tolerance, capable of efficiently hydrolyzing neutral and basic amino acids, while PfM17LAP has narrower substrate specificity and preferentially cleaves bulky, hydrophobic amino acids. The substrate library was also exploited to profile the activity of the native aminopeptidases in soluble cell lysates of P. falciparum malaria. Conclusions/Significance This data showed that PfM1AAP and PfM17LAP are responsible for majority of the aminopeptidase activity in these extracts. These studies provide specific substrate and mechanistic information important for understanding the function of these aminopeptidases and could be exploited in the design of new inhibitors to specifically target these for anti-malaria treatment. PMID:22359643

  6. A novel strain of Bacteroides fragilis enhances phagocytosis and polarises M1 macrophages

    Science.gov (United States)

    Deng, Huimin; Li, Zhengchao; Tan, Yafang; Guo, Zhaobiao; Liu, Yangyang; Wang, Ye; Yuan, Yuan; Yang, Ruifu; Bi, Yujing; Bai, Yang; Zhi, Fachao

    2016-01-01

    Commensal Bacteroides fragilis possesses immune-regulatory characteristics. Consequently, it has been proposed as a potential novel probiotic because of its therapeutic effects on immune imbalance, mental disorders and inflammatory diseases. Macrophages play a central role in the immune response, developing either a classical-M1 or an alternative-M2 phenotype after stimulation with various signals. The interactions between macrophages and B. fragilis, however, remain to be defined. Here, a new isolate of B. fragilis, ZY-312, was shown to possess admirable properties, including tolerance to simulated gastric fluid, intestinal fluid and ox bile, and good safety (MOI = 100, 200) and adherent ability (MOI = 100) to LoVo cells. Isolate ZY-312 cell lysate promoted phagocytosis of fluorescent microspheres and pathogenic bacteria in bone marrow-derived macrophage (BMDM) cells. Gene expression of IL-12, iNOS and IL-1β in BMDM cells was increased after treatment with ZY-312, indicating the induction of M1 macrophages, consistent with enhanced secretion of NO. Cell surface expression of CD80 and CD86 was also increased. This study is the first to demonstrate that B. fragilis enhances the phagocytic functions of macrophages, polarising them to an M1 phenotype. Our findings provide insight into the close relationship between B. fragilis and the innate immune system. PMID:27381366

  7. Tramadol differentially regulates M1 and M2 macrophages from human umbilical cord blood.

    Science.gov (United States)

    Zhang, Jun; Chen, Liang; Sun, Yunyun; Li, Yuanhai

    2017-03-17

    Tramadol is an analgesic drug and relieves pain through activating μ-opioid receptors and inhibiting serotonin and noradrenaline reuptake. Emerging evidence shows that it also stimulates immune cells, including NK cells, splenocytes, and lymphocytes, and elevates IL-2 production. However, it remains unknown whether and how tramadol directly affects macrophages. To answer these questions, we collected human umbilical cord blood, isolated macrophages, and examined their responses to tramadol. Although tramadol did not alter resting macrophages and the antigen-presenting function in lipopolysaccharide-activated macrophages, it regulated M1 and M2 macrophages, which are, respectively, transformed by IFN-γ and IL-4. Interestingly, tramadol inhibits production and secretion of cytokines in M1 macrophages, but facilitates the production of inflammation-responding molecules, synthesized in M2 macrophages. We also found that STAT6 cascade pathway in M2 macrophages was significantly enhanced by tramadol. Therefore, this study reveals that tramadol regulates inflammation by inhibiting M1 macrophages (killing process), but promoting the function of M2 macrophages (healing process).

  8. Muscarinic M1 receptors regulate propofol modulation of GABAergic transmission in rat ventrolateral preoptic neurons.

    Science.gov (United States)

    Zhang, Yu; Yu, Tian; Liu, Yang; Qian, Kun; Yu, Bu-Wei

    2015-04-01

    GABAergic neurons within the ventrolateral preoptic area (VLPO) play an important role in sleep-wakefulness regulation. Propofol, a widely used systemic anesthetic, has lately been reported to excite noradrenaline (NA)-inhibited type of VLPO neurons. Present study tested if acetylcholine system takes part in the propofol modulation of GABAergic spontaneous miniature inhibitory postsynaptic currents (mIPSCs) in mechanically dissociated rat VLPO neurons using a conventional whole-cell patch clamp technique. Propofol reversibly decreased mIPSC frequency without affecting the current amplitude, indicating that propofol acts presynaptically to decrease the probability of spontaneous GABA release. The propofol action on GABAergic mIPSC frequency was completely blocked by atropine, a nonselective muscarinic acetylcholine (mACh) receptor antagonist, and pirenzepine, a selective M1 receptor antagonist. These results suggest that propofol acts on M1 receptors on GABAergic nerve terminals projecting to VLPO neurons to inhibit spontaneous GABA release. The M1 receptor-mediated modulation of GABAergic transmission onto VLPO neurons may contribute to the regulation of loss of consciousness induced by propofol.

  9. Chronic treatment with simvastatin upregulates muscarinic M1/4 receptor binding in the rat brain.

    Science.gov (United States)

    Wang, Q; Zengin, A; Ying, W; Newell, K A; Wang, P; Yeo, W; Wong, P T-H; Yenari, M A; Huang, X-F

    2008-06-26

    Statins are increasingly being used for the treatment of a variety of conditions beyond their original indication for cholesterol lowering. We previously reported that simvastatin affected the dopaminergic system in the rat brain. This study aims to investigate regional changes of muscarinic M1/4 receptors in the rat brain after 4-week administration of simvastatin (1 or 10 mg/kg/day). M1/4 receptor distribution and alterations in the post-mortem rat brain were detected by [(3)H]pirenzepine binding autoradiography. Simvastatin (1 mg/kg/day) increased [(3)H]pirenzepine binding, predominantly in the prefrontal cortex (171%, Ppirenzepine binding were observed in the examined regions following simvastatin (10 mg/kg/day) treatment. Our results also provide strong evidence that chronic simvastatin administration, especially at a low dosage, up-regulates M1/4 receptor binding, which is likely to be independent of its muscarinic agonist-like effect. Alterations in [(3)H]pirenzepine binding in the examined brain areas may represent the specific regions that mediate the clinical effects of simvastatin treatment on cognition and memory via the muscarinic cholinergic system. These findings contribute to a better understanding of the critical roles of simvastatin in treating neurodegenerative disorders, via muscarinic receptors.

  10. The mechanism of the anticancer function of M1 macrophages and their use in the clinic

    Institute of Scientific and Technical Information of China (English)

    Xing-Qing Pan

    2012-01-01

    M1-type macrophages are capable of inducing lysis in various types of cancer cells,but the mechanism of action is unclear.It has been noted that an "unknown protein" produced together with protease by activated macrophages is responsible for this action.Activated M1 macrophages have been recently reported to produce family 18 chitinases,all of which have been named chitotriosidase.Our experiments have demonstrated that family 18 chitinases work together with proteases and can damage various cancer cells both in vitro and in vivo.Thus,in this article,we suggest that the 50-kDa chitotriosidase is the reported "unknown protein".In addition,we discuss how to properly stimulate activated M1 macrophages to produce 50-kDa chitotriosidases and proteases for destroying cancer cells.Because family 19 chitinase has recently been reported to kill cancer cells,we also discuss the possibility of directly using human family 18 chitotriosidase and the humanized plant family 19 chitinase for cancer treatment.

  11. The detection of C60 in the well-characterized planetary nebula M1-11

    CERN Document Server

    Otsuka, Masaaki; Hyung, S; Sargent, B A; Meixner, M; Tajitsu, A; Yanagisawa, K

    2013-01-01

    We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show features due to carbon-rich dust, such as the 3.3, 8.6, and 11.3 um features due to polycyclic aromatic hydrocarbons (PAHs), a smooth continuum attributable to amorphous carbon, and the broad 11.5 and 30 um features often ascribed to SiC and MgS, respectively. We also report the presence of an unidentified broad feature at 16-22 um, similar to the feature found in Magellanic Cloud PNe with either C-rich or O-rich gas-phase compositions. We identify for the first time in M1-11 spectral lines at 8.5 (blended with PAH), 17.3, and 18.9 um that we attribute to the C60 fullerene. This identification is strengthened by the fact that other Galactic PNe in which fullerenes are detected, have similar central stars, similar gas-phase abundances, and a similar dust composition to M1-11. T...

  12. Surface Termination of M1 Phase and Rational Design of Propane Ammoxidation Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Guliants, Vadim

    2015-02-16

    This final report describes major accomplishments in this research project which has demonstrated that the M1 phase is the only crystalline phase required for propane ammoxidation to acrylonitrile and that a surface monolayer terminating the ab planes of the M1 phase is responsible for their activity and selectivity in this reaction. Fundamental studies of the topmost surface chemistry and mechanism of propane ammoxidation over the Mo-V-(Te,Sb)-(Nb,Ta)-O M1 and M2 phases resulted in the development of quantitative understanding of the surface molecular structure – reactivity relationships for this unique catalytic system. These oxides possess unique catalytic properties among mixed metal oxides, because they selectively catalyze three alkane transformation reactions, namely propane ammoxidation to acrylonitrile, propane oxidation to acrylic acid and ethane oxidative dehydrogenation, all of considerable economic significance. Therefore, the larger goal of this research was to expand this catalysis to other alkanes of commercial interest, and more broadly, demonstrate successful approaches to rational design of improved catalysts that can be applied to other selective (amm)oxidation processes.

  13. Aflatoxin M1 in raw milk in Qazvin Province, Iran: a seasonal study.

    Science.gov (United States)

    Fallah, Aziz A; Barani, Afshin; Nasiri, Zeinab

    2015-01-01

    Occurrence of aflatoxin M1 (AFM1) was determined in 254 samples of raw milk obtained from dairy cow farms of Qazvin Province, Iran. Aflatoxin M1 analysis was carried out by using the competitive enzyme-linked immunosorbent assay technique for screening and high-performance liquid chromatography with fluorescence detection for confirmatory purposes. The limit of detection and quantification of the confirmatory method were 0.003 and 0.01 µg/l, respectively. Aflatoxin M1 was detected in 204 analysed samples (80.3%), ranging from 0.011 to 0.321 μg/l, and 144 samples (56.7%) had levels above the Iranian national standard limit of 0.050 μg/l. Considering the seasonal variability, the occurrence and levels of AFM1 in samples obtained in winter were significantly higher (P < 0.05) than those obtained in summer. The results of this survey indicate the usefulness of a monitoring programme to supervise food safety for consumers.

  14. Enhanced Macrophage M1 Polarization and Resistance to Apoptosis Enable Resistance to Plague.

    Science.gov (United States)

    Pachulec, Emilia; Abdelwahed Bagga, Rym Ben; Chevallier, Lucie; O'Donnell, Hope; Guillas, Chloé; Jaubert, Jean; Montagutelli, Xavier; Carniel, Elisabeth; Demeure, Christian E

    2017-09-15

    Susceptibility to infection is in part genetically driven, and C57BL/6 mice resist various pathogens through the proinflammatory response of their M1 macrophages (MPs). However, they are susceptible to plague. It has been reported elsewhere that Mus spretus SEG mice resist plague and develop an immune response characterized by a strong recruitment of MPs. The responses of C57BL/6 and SEG MPs exposed to Yersinia pestis in vitro were examined. SEG MPs exhibit a stronger bactericidal activity with higher nitric oxide production, a more proinflammatory polarized cytokine response, and a higher resistance to Y. pestis-induced apoptosis. This response was not specific to Y. pestis and involved a reduced sensitivity to M2 polarization/signal transducer and activator of transcription 6 activation and inhibition of caspase 8. The enhanced M1 profile was inducible in C57BL/6 MPs in vitro, and when transferred to susceptible C57BL/6 mice, these MPs significantly increased survival of bubonic plague. MPs can develop an enhanced functional profile beyond the prototypic M1, characterized by an even more potent proinflammatory response coordinated with resistance to killing. This programming plays a key role in the plague-resistance phenotype and may be similarly significant in other highly lethal infections, suggesting that orienting the MP response may represent a new therapeutic approach.

  15. Significance of settling model structures and parameter subsets in modelling WWTPs under wet-weather flow and filamentous bulking conditions.

    Science.gov (United States)

    Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen; Plósz, Benedek Gy

    2014-10-15

    Current research focuses on predicting and mitigating the impacts of high hydraulic loadings on centralized wastewater treatment plants (WWTPs) under wet-weather conditions. The maximum permissible inflow to WWTPs depends not only on the settleability of activated sludge in secondary settling tanks (SSTs) but also on the hydraulic behaviour of SSTs. The present study investigates the impacts of ideal and non-ideal flow (dry and wet weather) and settling (good settling and bulking) boundary conditions on the sensitivity of WWTP model outputs to uncertainties intrinsic to the one-dimensional (1-D) SST model structures and parameters. We identify the critical sources of uncertainty in WWTP models through global sensitivity analysis (GSA) using the Benchmark simulation model No. 1 in combination with first- and second-order 1-D SST models. The results obtained illustrate that the contribution of settling parameters to the total variance of the key WWTP process outputs significantly depends on the influent flow and settling conditions. The magnitude of the impact is found to vary, depending on which type of 1-D SST model is used. Therefore, we identify and recommend potential parameter subsets for WWTP model calibration, and propose optimal choice of 1-D SST models under different flow and settling boundary conditions. Additionally, the hydraulic parameters in the second-order SST model are found significant under dynamic wet-weather flow conditions. These results highlight the importance of developing a more mechanistic based flow-dependent hydraulic sub-model in second-order 1-D SST models in the future.

  16. Forkhead transcription factor FoxM1 regulates mitotic entry and prevents spindle defects in cerebellar granule neuron precursors

    NARCIS (Netherlands)

    Schueller, Ulrich; Zhao, Qing; Godinho, Susana A.; Heine, Vivi M.; Medema, Rene H.; Pellman, David; Rowitch, David H.

    2007-01-01

    The forkhead transcription factor FoxM1 has been reported to regulate, variously, proliferation and/or spindle formation during the G(2)/M transition of the cell cycle. Here we define specific functions of FoxM1 during brain development by the investigation of FoxM1 loss-of-function mutations in the

  17. Fast step-response settling of micro electrostatic actuators operated at low air pressure using input shaping

    Science.gov (United States)

    Mol, L.; Rocha, L. A.; Cretu, E.; Wolffenbuttel, R. F.

    2009-07-01

    Squeeze-film damping is highly inadequate in low-pressure systems or in systems where air pressure and/or gap dimensions are poorly defined. Input shaping has been used to circumvent the oscillations typically associated with under-damped mass-spring-damper systems and drastically decrease the settling time. The proposed method does not rely on feedback but solely on the system dynamics. The required input signal is derived analytically from the differential equation describing the system. The resulting device response is simulated and experimentally verified on an electrostatically actuated microstructure. Settling occurs even faster than for an equivalent critically damped system.

  18. Macrophage polarisation: an immunohistochemical approach for identifying M1 and M2 macrophages.

    Directory of Open Access Journals (Sweden)

    Mário Henrique M Barros

    Full Text Available Macrophage polarization is increasingly recognised as an important pathogenetic factor in inflammatory and neoplastic diseases. Proinflammatory M1 macrophages promote T helper (Th 1 responses and show tumoricidal activity. M2 macrophages contribute to tissue repair and promote Th2 responses. CD68 and CD163 are used to identify macrophages in tissue sections. However, characterisation of polarised macrophages in situ has remained difficult. Macrophage polarisation is regulated by transcription factors, pSTAT1 and RBP-J for M1, and CMAF for M2. We reasoned that double-labelling immunohistochemistry for the detection of macrophage markers together with transcription factors may be suitable to characterise macrophage polarisation in situ. To test this hypothesis, we have studied conditions associated with Th1- and Th2-predominant immune responses: infectious mononucleosis and Crohn's disease for Th1 and allergic nasal polyps, oxyuriasis, wound healing and foreign body granulomas for predominant Th2 response. In all situations, CD163+ cells usually outnumbered CD68+ cells. Moreover, CD163+ cells, usually considered as M2 macrophages, co-expressing pSTAT1 and RBP-J were found in all conditions examined. The numbers of putative M1 macrophages were higher in Th1- than in Th2-associated diseases, while more M2 macrophages were seen in Th2- than in Th1 related disorders. In most Th1-related diseases, the balance of M1 over M2 cells was shifted towards M1 cells, while the reverse was observed for Th2-related conditions. Hierarchical cluster analysis revealed two distinct clusters: cluster I included Th1 diseases together with cases with high numbers of CD163+pSTAT1+, CD68+pSTAT1+, CD163+RBP-J+ and CD68+RBP-J+ macrophages; cluster II comprised Th2 conditions together with cases displaying high numbers of CD163+CMAF+ and CD68+CMAF+ macrophages. These results suggest that the detection of pSTAT1, RBP-J, and CMAF in the context of CD68 or CD163 expression is a

  19. Production of a monoclonal antibody against aflatoxin M1 and its application for detection of aflatoxin M1 in fortified milk

    Directory of Open Access Journals (Sweden)

    Umarphorn Chadseesuwan

    2016-10-01

    Full Text Available Aflatoxin M1 (AFM1 is a toxic metabolite of the fungal product aflatoxin found in milk. For food safety concern, maximum residual limits of AFM1 in milk and dairy products have been differently enforced in many countries. A suitable detection method is required to screen a large number of product samples for the AFM1 contamination. In this study, monoclonal antibodies (MAbs against AFM1 were generated using a conventional somatic cell fusion technique. After screening, five MAbs (AFM1-1, AFM1-3, AFM1-9, AFM1-11, and AFM1-17 were obtained that showed cross-reactivity with aflatoxin B1 (AFB1 and aflatoxin G1 (AFG1 but with no other tested compounds. An indirect competitive enzyme-linked immunosorbent assay (ELISA using a partially purified MAb and antigen-coated plates yielded the best sensitivity with the 50% inhibition concentration (IC50 and the limit of detection (LOD values of 0.13 ng/mL and 0.04 ng/mL, respectively. This indirect competitive ELISA was used to quantify the amount of fortified AFM1 in raw milk. The precision and accuracy in terms of % coefficient of variation (CV and % recovery of the detection was investigated for both intra- (n = 6 and inter- (n = 12 variation assays. The % CV was found in the range of 3.50–15.8% and 1.32–7.98%, respectively, while the % recovery was in the range of 92–104% and 100–103%, respectively. In addition, the indirect ELISA was also used to detect AFM1 fortified in processed milk samples. The % CV and % recovery values were in the ranges of 0.1–33.0% and 91–109%, respectively. Comparison analysis between the indirect ELISA and high performance liquid chromatography was also performed and showed a good correlation with the R2 of 0.992 for the concentration of 0.2–5.0 ng/mL. These results indicated that the developed MAb and ELISA could be used for detection of AFM1 in milk samples.

  20. Ethics control of vertebrate animals experiments in biosatellite BION-M1 project

    Science.gov (United States)

    Ilyin, Eugene

    During April 19-May 19, 2013 it was realized 30-days flight of Russian biosatellite Bion-M1. The main goal of this flight was to study effects of microgravity upon behavior and structural-functional state of different physiological systems of vertebrates. The folloving species were accommodated aboard of biosatellite: 45 mice C57bl/6, 8 Mongolian gerbils Meriones unguiculatus, 15 lizards, i.e. geckos Chondrodctylus turneri Gray, and fish Oreochromis mossambicus. The selection and traing of mice for the flight and ground-based control experiments was carried out at the Research Institute of Mitoengineering by Moscow State University. The protocols for animals care and reserch were revised and adopted by Bioethics Commission of above mentioned institute (decision on November 01, 2013, N35). The final version of Bion-M1 Scientific Reseach Program and protocols for separate experiments were discussed and adopted by Biomedical Ethics Commission of Institute of Biomedical Problems (decision on April 4, 2014, N317). The IMBP Commission has a status of Physiological Section of Russian Bioethics Committee by Russian Commision for UNESCO affairs and follows the Russian Bioethical Guidelines for Experiments in Aerospace and Naval Medicine and other national and international rules including COSPAR International Policy and Guidelines for Animal Care and Use in Space-born Research. Because US-scientists were the main partners in mice investigations the decision of IMBP Biomedical Commission related to Bion-M1 project was sended for information to Institutional Animal Care and Use Committee of NASA Ames Research Center. Postflight estimation of mice was done by Russian veterinary with the participation of NASA Chief veterinary.

  1. Effect of pirenzepine, a muscarinic M1 receptor antagonist, on amygdala kindling in rat.

    Science.gov (United States)

    Eşkazan, E; Aker, R; Onat, F; Köseoğlu, S; Gören, M Z; Hasanoğlu, A

    1999-11-01

    Kindling, an animal model of complex partial seizures with secondary generalization, is performed by daily application of low-intensity electrical brain stimulation. The purpose of this study was to investigate the role of muscarinic M1 receptors on amygdala kindling in the rat. Bipolar nichrome stimulation and recording electrodes were stereotaxically implanted into the right and left basolateral amygdala. Extradural recording electrodes were also placed bilaterally in the skull over the cortex. Amygdala stimulation was applied twice daily at the current intensity of afterdischarge threshold. Seizure intensity was graded by using Racine's standard five-stage scale. In the first group of experiments, saline or pirenzepine (10, 25, 50 and 100 nmol), a muscarinic M1 receptor antagonist, was injected intracerebroventricularly 1 h before the electrical stimulation. In the second group of experiments, rats were kindled to full stage 5 seizures. After a recovery period, 50 nmol of pirenzepine was administered intracerebroventricularly to kindled animals. In the first group of experiments, none of the animals pretreated with the doses of 50 and 100 nmol of pirenzepine reached a stage 5 seizure. Pirenzepine significantly retarded kindling seizure development and increased the total number of stimulations required to reach the first stage 5 seizure. Afterdischarge duration was also reduced in the pirenzepine 10 nmol group as compared with that in the saline-pretreated group. In the second group, seizure stage and afterdischarge duration were not affected by pirenzepine in fully-kindled animals. The findings of this study suggest that muscarinic M1 receptors may have a critical role in the development of kindling epileptic activity, but not in already kindled seizures.

  2. Spatio-kinematics of the optical nebula M1-92 with HST/STIS

    Science.gov (United States)

    Ramos-Medina, J.; Sánchez-Contreras, C.; Sahai, R.; Bujarrabal, V.; Castro-Carrizo, A.; Morris, M.

    2014-04-01

    We report optical long-slit spectroscopy with HST/STIS of the well known pre-Planetary Nebula (pPN) M1-92 (a.k.a. Minkowski's footprint). Complementary long-slit echelle spectra obtained with Keck II+ESI have been also used. We have used our high-angular (~0.1arcsec) resolution spectra to characterize the spatio-kinematic structure of the optical nebula of this object. From the analysis of the Halpha two-dimensional profile we identify several distinct nebular components at different spatial scales. The blue-shifted absorption component of the broad 'P cygni'-like profile of the Halpha emission is spatially and spectrally resolved and is found to be composed of not one but two different features centered at Vlsr~-600 and -200 km/s. To assist in the interpretation of the data, we have used a simple spatio-kinematic model which has allowed us to describe the main properties of the fast, bipolar winds (expanding with velocities of up to ~700 km/s) running inside the reflection lobes of M1-92 and that produce the absorptions. At the nebula center, we also discover an equatorially extended H-alpha emitting region that is expanding at moderate velocity (~300 km/s) in the direction perpendicular to the lobes. We have estimated the column density of the inner post-AGB winds and other physical parameters that have helped improving our understanding of the evolutionary history of M1-92.

  3. Relationship between pattern of ischemic manifestation and hemodynamics in symptomatic M1 stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Tokumitsu, Naoki; Sako, Kazuhiro; Aizawa, Shizuka; Shirai, Wakako [Nayoro City Hospital, Hokkaido (Japan)

    2002-07-01

    The mechanism through which ischemic manifestations develop in patients with middle cerebral artery (MCA) stenosis is still uncertain. It may cause ischemic symptoms through both embolic and hemodynamic mechanisms. In this study, we compared the findings from cerebral angiograms with single photon emission computed tomography (SPECT) in patients with M1 stenosis to determine the pathogenesis of ischema. At our hospital from 1994 to 2000, 14 patients (12 males and 2 females; mean age, 60.9; range, 31 to 85 years) with angiographically demonstrated symptomatic M1 stenosis were enrolled in this study. In 10, their stenotic lesion was located at the proximal site of the perforating arteries and for the other 4, stenosis was found at the distal site. Nine presented with transient ischemic attack (TIA) and 5 with completed stroke for an initial episode. The discrepancy in regional cerebral blood flow (rCBF) was evaluated in relation to the site and degree of stenosis, type of ischemic presentation, and frequency of ischemic events. There was no significant difference in CBF between the patients with stenosis involving the proximal site and those with distal stenosis; but the cortical CBF decreased significantly in those with severe stenosis compared with moderate stenosis. The cortical CBF of those who had a complete stroke is similar to that of the patients with TIA; but CBF of BGA decreased significantly in those with a complete stroke. The single ischemic event group showed a significant decrease in cortical CBF. On the other hand, the group with multiple ischemic events exhibited normal hemodynamics. We concluded that multiple ischemic events that occurred in M1 stenosis are caused by an embolic mechanism. (author)

  4. ISSR Analysis of M_1 Generation of Gladiolus hybridus Hort Treated by EMS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Gladiolus hybridus Hort is one of famous cutting flowers,being famous of big size,bright color,various shapes and long bloom period.New species should be cultivated in order to meet consumers' needs.Mutagenic breeding is a shortcut to cultivate new species of flowers.In this study,corm bud of G.hybridus Hort was treated with different concentrations of EMS.Then M 1 generation was analyzed by ISSR.Results showed that EMS was a very effective mutagenic agent for the corm bud of G.hybridus Hort.With the increa...

  5. Aflatoxin M1 level in pasteurized and sterilized milk of Babol city

    Directory of Open Access Journals (Sweden)

    Hashemi S J

    2007-11-01

    Full Text Available Background: Aflatoxins are severe toxic secondary metabolites found in most plant products. When animals consume contaminated feed stuff to Aflatoxin B1 (AFB1, the toxin is metabolized by liver and is excreted as Aflatoxin M1 (AFM1 via milk. Aflatoxins are acute toxic compounds, immunosuppressive, mutagen, tratogen and carcinogen."nMethods: During the winter of 2006, pasteurized and sterilized (ultra high temperature (UHT milk packages were collected from supermarkets in Babol city. 78 pasteurized and 33 sterilized milk, totally 111 samples were tested for AFM1 by competitive Enzyme Linked Immunosorbent Assay (ELISA. Solid phase in plastic micro wells coated whit anti-Aflatoxin M1 antibodies. We added 100 microliter skimmed milk and Aflatoxin M1 standard solutions in each well. In each plate, we appointed seven wells for standards. Plates were incubated at 20-25 centigrade for 45 min. Each well was washed four times by washing buffer 20X concentration. Then 100 micro liter conjugated solution (100X was added to each well, and the plate was incubated at 20-25 centigrade for 15 min. After that, the wells were washed. After adding the substrates to wells, we incubated the plate at 20-25 centigrade in a dark place for 15 min. The reaction was stopped by stop solution. After one hour, light absorption was read at 450 nm by ELISA reader."nResults: AFM1 were detected in 100% of all samples. 100% of samples were above of European community regulations (50ng/l. AFM1 contamination mean levels pasteurized and sterilized milk were 230.5 and 221.66 respectively. Therefore more than four fold levels European community. There is not a significant relationship between AFM1 contamina-tion level and different months of winter applying statistical test."nConclusion: The results showed the need for introducing safety limits for AFM1 levels in child milk under Food Legislative liable of Iran. Aflatoxin M1 contamination is a serious problem for public health

  6. Daniel Hertz SA M1落地式音箱

    Institute of Scientific and Technical Information of China (English)

    许成文

    2011-01-01

    Daniel Hertz SA M1落地式音箱在箱体结构上取经典造型。毫无疑问,Daniel Hertz的SAM1落地式音箱甫一亮相干市场,便已经奠定了它作为一代经典作品的基础——这不仅使其采用最经典的前障板布局和单元配置,在更大的程度上还包括它的综合技术内涵。

  7. THE DETECTION OF C60 IN THE WELL-CHARACTERIZED PLANETARY NEBULA M1-11

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Masaaki; Kemper, F. [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Hyung, S. [School of Science Education (Astronomy), Chungbuk National University, CheongJu, Chungbuk 361-763 (Korea, Republic of); Sargent, B. A.; Meixner, M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Tajitsu, A. [Subaru Telescope, NAOJ, 650 North A' ohoku Place, Hilo, HI 96720 (United States); Yanagisawa, K., E-mail: otsuka@asiaa.sinica.edu.tw [Okayama Astrophysical Observatory (OAO), NAOJ, Kamogata, Okayama 719-0232 (Japan)

    2013-02-10

    We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show features due to carbon-rich dust, such as the 3.3, 8.6, and 11.3 {mu}m features due to polycyclic aromatic hydrocarbons (PAHs), a smooth continuum attributable to amorphous carbon, and the broad 11.5 and 30 {mu}m features often ascribed to SiC and MgS, respectively. We also report the presence of an unidentified broad feature at 16-22 {mu}m, similar to the feature found in Magellanic Cloud PNe with either C-rich or O-rich gas-phase compositions. We identify for the first time in M1-11 spectral lines at 8.5 (blended with PAH), 17.3, and 18.9 {mu}m that we attribute to the C{sub 60} fullerene. This identification is strengthened by the fact that other Galactic PNe in which fullerenes are detected have similar central stars, similar gas-phase abundances, and a similar dust composition to M1-11. The weak radiation field due to the relatively cool central stars in these PNe may provide favorable conditions for fullerenes to survive in the circumstellar medium. Using the photoionization code CLOUDY, combined with a modified blackbody, we have fitted the {approx}0.1-90 {mu}m spectral energy distribution (SED) and determined the dust mass in the nebula to be {approx}3.5 Multiplication-Sign 10{sup -4} M {sub Sun }. Our chemical abundance analysis and SED model suggest that M1-11 is perhaps a C-rich PN with C/O ratio in the gas phase of +0.19 dex, and that it evolved from a 1-1.5 M {sub Sun} star.

  8. Scaled-energy spectroscopy of helium \\|M\\|=1 Rydberg atoms in a static electric field

    Science.gov (United States)

    Kips, Annemieke; Vassen, Wim; Hogervorst, Wim; Dando, Paul A.

    1998-10-01

    We present scaled-energy spectra on helium Rydberg atoms in a static electric field. \\|M\\|=1 states were studied in excitation from the 2 1S0 metastable state. Spectra were recorded for ɛ=-2.940(4), ɛ=-2.350(4), both below the saddle point, and ɛ=-1.760(4), above the saddle point. Closed-orbit theory was applied to interpret the spectra. A recent extension to closed-orbit theory, incorporating core effects, was used. This significantly improved agreement between experiment and theory.

  9. Enhancement of M1 Transition Rates at High Spin in 90Mo

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Guang; YANG Chun-Xiang; LI Guang-Sheng; PENG Zhao-Hua; WEN Shu-Xian; HAN Guang-Bing; LI Cheng-Po; LU Shao-Jun; WU Shao-Yong; YUAN Guan-Jun

    2001-01-01

    High spin states in 90Mo have been populated through the 59Co (35C1,2p2n) 90Mo reaction at a beam energy of116 Me V. Level lifetimes of the positive-parity decay sequence are measured by using the Doppler shift attenuationmethod. It is observed that the M1 transition strengths show a substantial enhancement at high spin. Thisbehaviour may be related to occupation of high Ω orbitals by a pair of g9/2 protons. A deformed, oblate, shapeis suggested above the 13+ state.

  10. Asymmetric Mach-Zehnder Interferometer Based Biosensors for Aflatoxin M1 Detection.

    Science.gov (United States)

    Chalyan, Tatevik; Guider, Romain; Pasquardini, Laura; Zanetti, Manuela; Falke, Floris; Schreuder, Erik; Heideman, Rene G; Pederzolli, Cecilia; Pavesi, Lorenzo

    2016-01-06

    In this work, we present a study of Aflatoxin M1 detection by photonic biosensors based on Si₃N₄ Asymmetric Mach-Zehnder Interferometer (aMZI) functionalized with antibodies fragments (Fab'). We measured a best volumetric sensitivity of 10⁴ rad/RIU, leading to a Limit of Detection below 5 × 10(-7) RIU. On sensors functionalized with Fab', we performed specific and non-specific sensing measurements at various toxin concentrations. Reproducibility of the measurements and re-usability of the sensor were also investigated.

  11. AN M/M/1/N FEEDBACK QUEUING SYSTEM WITH REVERSE BALKING

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar

    2015-06-01

    Full Text Available In this paper we develop an M/M/1/N feedback queuing system with reverse balking. Reverse balking is a type of customer behavior according to which an arriving customer joins a system with high probability if he encounters large system size and vice-versa. This behavior of a customer can be observed in many businesses such as investment. Feedback customer in queuing literature refers to a customer who is unsatisfied with incomplete, partial or unsatisfactory service. We derive the steady-state solution of the model and obtain some important measures of performance. Sensitivity analysis of the model is also performed with respect to the parameters involved.

  12. E1M1 and E1E2 transition probabilities in one-electron ions

    Science.gov (United States)

    Labzowsky, L. N.; Shonin, A. V.

    2004-12-01

    The quantum electrodynamical (QED) theory of the two-photon transitions in hydrogenlike ions is presented. The emission probability for 2s→2γ(E1)+1s transitions is calculated and compared to the results of the previous calculations. The emission probabilities 2p→γ(E1)+γ(E2)+1s and 2p→γ(E1)+γ(M1)+1s are also calculated for the nuclear charge Z values 1⩽Z⩽100. This is the first calculation of the two latter probabilities. The results are given in two different gauges.

  13. STS-34 crewmembers sit in M1-13 APC during emergency egress training at KSC

    Science.gov (United States)

    1989-01-01

    STS-34 crewmembers sit in M1-13 Armored Personnel Carrier (APC) during emergency egress training at KSC's shuttle landing facility (SLF) prior to terminal countdown demonstration test (TCDT) activities. Wearing launch and entry suits (LESs), are (from left) Mission Specialist (MS) Ellen S. Baker, MS Shannon W. Lucid, Commander Donald E. Williams (right side, in back), MS Franklin R. Chang-Diaz, and Pilot Michael J. McCulley (holding headset). View provided by KSC with alternate number KSC-89PC-871.

  14. The M/M/1 queue with inventory, lost sale and general lead times

    DEFF Research Database (Denmark)

    Saffari, Mohammad; Asmussen, Søren; Haji, Rasoul

    We consider an M/M/1 queueing system with inventory under the (r,Q) policy and with lost sales, in which demands occur according to a Poisson process and service times are exponentially distributed. All arriving customers during stockout are lost. We derive the stationary distributions of the joi...... queue length (number of customers in the system) and on-hand inventory when lead times are random variables and can take various distributions. The derived stationary distributions are used to formulate long-run average performance measures and cost functions in some numerical examples....

  15. Influence of secondary settling tank performance on suspended solids mass balance in activated sludge systems.

    Science.gov (United States)

    Patziger, M; Kainz, H; Hunze, M; Józsa, J

    2012-05-01

    Secondary settling is the final step of the activated sludge-based biological waste water treatment. Secondary settling tanks (SSTs) are therefore an essential unit of producing a clear effluent. A further important function of SSTs is the sufficient thickening to achieve highly concentrated return sludge and biomass within the biological reactor. In addition, the storage of activated sludge is also needed in case of peak flow events (Ekama et al., 1997). Due to the importance of a high SST performance the problem has long been investigated (Larsen, 1977; Krebs, 1991; Takács et al., 1991; Ekama et al., 1997; Freimann, 1999; Patziger et al., 2005; Bürger et al., 2011), however, a lot of questions are still to solve regarding e.g. the geometrical features (inflow, outflow) and operations (return sludge control, scraper mechanism, allowable maximum values of surface overflow rates). In our study we focused on SSTs under dynamic load considering both the overall unsteady behaviour and the features around the peaks, investigating the effect of various sludge return strategies as well as the inlet geometry on SST performance. The main research tool was a FLUENT-based novel mass transport model consisting of two modules, a 2D axisymmetric SST model and a mixed reactor model of the biological reactor (BR). The model was calibrated and verified against detailed measurements of flow and concentration patterns, sludge settling, accompanied with continuous on-line measurement of in- and outflow as well as returned flow rates of total suspended solids (TSS) and water. As to the inlet arrangement a reasonable modification of the geometry could result in the suppression of the large scale flow structures of the sludge-water interface thus providing a significant improvement in the SST performance. Furthermore, a critical value of the overflow rate (q(crit)) was found at which a pronounced large scale circulation pattern develops in the vertical plane, the density current in

  16. 29 CFR 1471.635 - May the Federal Mediation and Conciliation Service settle a debarment or suspension action?

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false May the Federal Mediation and Conciliation Service settle a...) FEDERAL MEDIATION AND CONCILIATION SERVICE GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) General Principles Relating to Suspension and Debarment Actions § 1471.635 May the Federal Mediation...

  17. 41 CFR 105-68.635 - May the General Services Administration settle a debarment or suspension action?

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false May the General Services Administration settle a debarment or suspension action? 105-68.635 Section 105-68.635 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL...

  18. Firearm bullet settling into the lumbar spinal canal without causing neurological deficit: A report of two cases

    Directory of Open Access Journals (Sweden)

    Tayfun Hakan

    2016-01-01

    Conclusion: Bullet settling into the lumbar spinal canal without causing neurological deficit may require surgical intervention. Removal of bullets provided not only pain relief in both the cases but also prevented future complications such as migration of the bullets, plumbism, and neuropathic pain and instability.

  19. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer at the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.

  20. EFFECT OF WATER CONTENT, TEMPERATURE AND AVERAGE DROPLET SIZE ON THE SETTLING VELOCITY OF WATER-IN-OIL EMULSIONS

    Directory of Open Access Journals (Sweden)

    W. J. Souza

    2015-06-01

    Full Text Available AbstractWater-in-oil (W/O emulsions are complex mixtures generally found in crude oil production in reservoirs and processing equipment. Sedimentation studies of water-oil emulsions enable the analysis of the fluid dynamic behavior concerning separation of this system composed of two immiscible liquids. Gravitational settling was evaluated in this article for a model emulsion system consisting of water and a Brazilian crude oil diluted in a clear mineral oil as organic phase. The effects of water content and temperature were considered in the study of sedimentation velocity of water-oil emulsions. Water contents between 10% and 50 % and temperatures of 25, 40 and 60 ºC were evaluated, and a Richardson-Zaki type correlation was obtained to calculate settling velocities as a function of the process variables investigated. Water contents and average droplet sizes were monitored at different levels in the settling equipment, thus enabling identification of the effect of these variables on the phenomena of sedimentation and coalescence of the emulsions studied. The results showed that the emulsion stability during sedimentation was governed by the emulsion water content, which yielded high settling velocities at low water contents, even when very small droplets were present. A quantitative analysis of the combined effects of drop size and droplet concentration supports the conclusion that a stronger effect is produced by the higher concentration of particles, compared with the relatively smaller effect of increasing the size of the droplets.

  1. Fast step-response settling of micro electrostatic actuators operated at low air pressure using input shaping

    NARCIS (Netherlands)

    Mol, L.; Rocha, L.A.; Cretu, E.; Wolffenbuttel, R.F.

    2009-01-01

    Squeeze-film damping is highly inadequate in low-pressure systems or in systems where air pressure and/or gap dimensions are poorly defined. Input shaping has been used to circumvent the oscillations typically associated with under-damped mass-spring-damper systems and drastically decrease the settl

  2. Elevated hair cortisol concentrations in recently fled asylum seekers in comparison to permanently settled immigrants and non-immigrants.

    Science.gov (United States)

    Mewes, R; Reich, H; Skoluda, N; Seele, F; Nater, U M

    2017-03-07

    Recently fled asylum seekers generally live in stressful conditions. Their residency status is mostly insecure and, similar to other immigrants, they experience stress due to acculturation. Moreover, they often suffer from traumatization and posttraumatic stress disorder (PTSD). All of these factors can result in chronic maladaptive biological stress responses in terms of hyper- or hypocortisolism and, ultimately, illness. We believe the current study is the first to compare hair cortisol concentration (HCC) of recently fled asylum seekers with PTSD to those without PTSD, and to compare HCC of asylum seekers to HCC of permanently settled immigrants and non-immigrant individuals. HCC of the previous 2 months was compared between 24 asylum seekers without PTSD, 32 asylum seekers with PTSD, 24 permanently settled healthy Turkish immigrants and 28 non-immigrant healthy Germans as the reference group. Statistical comparisons were controlled for age, sex and body mass index. No significant difference in HCC was found between asylum seekers with and without PTSD. However, the asylum seekers showed a 42% higher HCC than the reference group. In contrast, the permanently settled immigrants exhibited a 23% lower HCC than the reference group. We found relative hypercortisolism in recently fled asylum seekers, but no difference between persons with and without PTSD. These findings add to the very few studies investigating HCC in groups with recent traumatization and unsafe living conditions. Contrary to the findings in asylum seekers, permanently settled immigrants showed relative hypocortisolism. Both hyper- and hypocortisolism may set the stage for the development of stress-related illnesses.

  3. Numerical simulation of flocculation and settling behavior of whole-tailings particles in deep-cone thickener

    Institute of Scientific and Technical Information of China (English)

    RUAN Zhu-en; LI Cui-ping; SHI Cong

    2016-01-01

    Rapid dewatering and thickening of whole-tailings with ultrafine particles is one of the most important processes for the whole-tailings paste preparation. Deep-cone thickener, a kind of such process for the flocculation and settling of whole-tailings, is particularly necessary to study. However, there exist many problems in observing the flocculation and settling process of whole-tailings, as well as the particle size distribution (PSD) of whole-tailings floccules in deep-cone thickener. Population balance model (PBM) is applied to predict the PSD in deep-cone thickener, and LUO model and GHADIRI model are employed to study the aggregation and fragmentation mechanism of the whole-tailings particles, respectively. Through three-dimensional numerical simulation on the whole-tailings flocculation and settling in deep-cone thickener using computational fluid dynamics (CFD)-PBM, the distribution of density and turbulent kinetic energy in deep-cone thickener were obtained, at the same time the spatio-temporal changes of whole-tailings floccules particle size distribution are analyzed. Finally, the major flocculation position in deep-cone thickener is found and the flocculation settling rules of whole-tailings are achieved.

  4. IMPACT OF PARTICLE SIZE AND AGGLOMERATION ON SETTLING OF SOLIDS IN CONTINUOUS MELTERS PROCESSING RADIOACTIVE WASTE GLASS

    Energy Technology Data Exchange (ETDEWEB)

    HRMA PR

    2008-12-18

    The major factor limiting waste loading for many waste compositions in continuous waste glass melters is the settling of crystalline materials. The currently used constraints, i.e., the minimum liquidus temperature or the maximum fraction of equilibrium crystallinity at a given temperature, are based on thennodynamic equilibria. Because of the rapid circular convection in the melter, these constraints are probably irrelevant and cannot prevent large crystals from settling. The main factor that detennines the rate of settling ofindividual crystals, such as those ofspinel, is their size. The tiny crystals of RU02 are too small to settle, but they readily fonn large agglomerates that accelerate their rate ofsettling by severalorders ofmagnitude. The RU02 agglomerates originate early in the melting process and then grow by the shear-flocculation mechanism. It is estimated that these agglomerates must either be ofhundreds micrometers in size or have an elongated shape to match the observed rates ofthe sludge-layer fonnation. PACS: 47.57.ef, 81.05.Kj, 81.10.Fg

  5. Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Fowley, M. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Miller, D. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-05-01

    The full scale, room temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer at the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.

  6. Assessment and forecast of changes of reservoir volumes due to thermal settling in permafrost areas of Russia

    Institute of Scientific and Technical Information of China (English)

    Ilja S.Sobol; Stanislav V.Sobol

    2014-01-01

    This paper presents the results of data analyses and assessments of field and theoretical researches on reservoir bed relief transformation due to thermal settling in the permafrost regions of Russia. The resulting changes (increases) of the total volumes of large and small reservoirs are quantified, of which information will be of great use in future reservoir design and exploitation.

  7. Numerical and Experimental Studies of Particle Settling in Real Fracture Geometries

    Science.gov (United States)

    Roy, Pratanu; Du Frane, Wyatt L.; Kanarska, Yuliya; Walsh, Stuart D. C.

    2016-11-01

    Proppant is a vital component of hydraulic stimulation operations, improving conductivity by maintaining fracture aperture. While correct placement is a necessary part of ensuring that proppant performs efficiently, the transport behavior of proppant in natural rock fractures is poorly understood. In particular, as companies pursue new propping strategies involving new types of proppant, more accurate models of proppant behavior are needed to help guide their deployment. A major difficulty with simulating reservoir-scale proppant behavior is that continuum models traditionally used to represent large-scale slurry behavior loose applicability in fracture geometries. Particle transport models are often based on representative volumes that are at the same scale or larger than fractures found in hydraulic fracturing operations, making them inappropriate for modeling these types of flows. In the absence of a first-principles approach, empirical closure relations are needed. However, even such empirical closure relationships are difficult to derive without an accurate understanding of proppant behavior on the particle level. Thus, there is a need for experiments and simulations capable of probing phenomena at the sub-fracture scale. In this paper, we present results from experimental and numerical studies investigating proppant behavior at the sub-fracture level, in particular, the role of particle dispersion during proppant settling. In the experimental study, three-dimensional printing techniques are used to accurately reproduce the topology of a fractured Marcellus shale sample inside a particle-flow cell. By recreating the surface in clear plastic resin, proppant movement within the fracture can be tracked directly in real time without the need for X-ray imaging. Particle tracking is further enhanced through the use of mixtures of transparent and opaque proppant analogues. The accompanying numerical studies employ a high-fidelity three-dimensional particle-flow model

  8. The Effects of Ore Properties on the Characterization of Suspension in Settling and Compression

    Directory of Open Access Journals (Sweden)

    Majid Unesi

    2014-06-01

    Full Text Available Many studies have considered the effects of suspension properties on the dewatering process but fewhave focused on ore properties. Thus, the present work studied the effects of ore properties (density,particle size, mineralogy on the dewatering process based on lab and pilot experiments. A hydrocyclonewas used to prepare the required samples for the experiments. To study the effects of mineralogicalproperties, the sedimentation behaviour of hydrocyclone feed and underflow samples were compared. Itwas observed that the free-settling velocity of feed (2 to 6mm/sec was less than in the underflow sample(2 to 7mm/sec and the final concentration of underflow sample (0.45 to 0.48t/m3 was more than thefeed sample (0.44 to 0.47t/m3. Additionally, to study the effects of particle size and density, thesedimentation behaviour of hydrocyclone overflow and feed samples were compared. The settlingvelocity and final concentration of overflow sample were obtained at 0.15 to 0.4mm/sec and 0.32t/m3,respectively, which was significantly less than the feed sample. This was due to the amount of clayreduction in the underflow sample and particle size and density reduction in the overflow sample.Following on, the pilot experiments were carried out. It was observed that the bed formation of the feedsample tended to overflow in the sample at low flux (10t/m2/day and tended to underflow in the sampleat high flux (28.5t/m2/day. This meant that the long time at lower flux created an opportunity for fineparticles to settle easily, similar to coarser particles and as such, ore properties did not play a decisiverole in bed formation, but their effects appeared instead at higher flux. Furthermore, it was observed thatthe underflow concentration increased by decreasing the flux from 28.5 to 10t/m2/day. These increasingamounts were 0.05t/m3 and 0.12t/m3 in hydrocyclone overflow and underflow samples, respectively, at aheight of 2.5 metres. This meant that the compressibility and

  9. M1-46: A Case Study on Multiple-Shell Planetary Nebula Formation

    Science.gov (United States)

    Guerrero, M. A.; Manchado, A.; Stanghellini, L.; Herrero, A.

    1996-06-01

    We discuss in detail the evolutionary path of the multiple-shell planetary nebula M1-46, in the light of our new observations. The velocities of the halo and main nebula correspond to a dynamical time lap between the shells of about 6.8 x 104 yr. By means of a non-LTE analysis of the central star's spectrum, we derived a stellar temperature of Teff = 45,000 K, which, coupled to the visual magnitude and an appropriate bolometric correction, gives a stellar luminosity of 5370 Lsun. The mass of the central star has been evaluated to be 0.6 Msun, and its interpulse time on the asymptotic giant branch is 7.6 x 104 yr. The agreement between the observed intershell time lap and the evolutionary interpulse time lap points to the fact that the formation of this planetary nebula could be ascribed to the gasping mass loss associated with the thermal pulses at the thermally pulsating asymptotic giant branch. The high-resolution spatially resolved observations reveal the presence of different kinematical components in the main nebula which cannot be understood in a homogeneous expanding shell scenario. As regards the chemical abundances, M1-46 has the typical abundances of a type II planetary nebula. No definite abundance gradient between the shells is found.

  10. Structural basis for the inhibition of the essential Plasmodium falciparum M1 neutral aminopeptidase

    Science.gov (United States)

    McGowan, Sheena; Porter, Corrine J.; Lowther, Jonathan; Stack, Colin M.; Golding, Sarah J.; Skinner-Adams, Tina S.; Trenholme, Katharine R.; Teuscher, Franka; Donnelly, Sheila M.; Grembecka, Jolanta; Mucha, Artur; Kafarski, Pawel; DeGori, Ross; Buckle, Ashley M.; Gardiner, Donald L.; Whisstock, James C.; Dalton, John P.

    2009-01-01

    Plasmodium falciparum parasites are responsible for the major global disease malaria, which results in >2 million deaths each year. With the rise of drug-resistant malarial parasites, novel drug targets and lead compounds are urgently required for the development of new therapeutic strategies. Here, we address this important problem by targeting the malarial neutral aminopeptidases that are involved in the terminal stages of hemoglobin digestion and essential for the provision of amino acids used for parasite growth and development within the erythrocyte. We characterize the structure and substrate specificity of one such aminopeptidase, PfA-M1, a validated drug target. The X-ray crystal structure of PfA-M1 alone and in complex with the generic inhibitor, bestatin, and a phosphinate dipeptide analogue with potent in vitro and in vivo antimalarial activity, hPheP[CH2]Phe, reveals features within the protease active site that are critical to its function as an aminopeptidase and can be exploited for drug development. These results set the groundwork for the development of antimalarial therapeutics that target the neutral aminopeptidases of the parasite. PMID:19196988

  11. 新加坡M1与Vodafone达成漫游协议

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    为了让经常旅游的客户能够更方便有效地使用数据业务。新加坡M1用户推出了数据漫游业务。用户在Vodafone的网络上进行数据漫游时,将只需支付本地数据资费,从而节省了60%的数据使用费。这一优惠目前可以在8个有Vodafone网络运营的国家实现,今年早些时候将有超过30个国家可以享受到这项服务,包括一些很流行的漫游目的地,如香港、法国、英国、澳大利亚和德国。随着数据漫游资费的推出,M1成为新加坡第一个提供在Vodafone网络上的单一数据漫游资费的移动运营商。

  12. Structural basis for the inhibition of the essential Plasmodium falciparum M1 neutral aminopeptidase.

    Science.gov (United States)

    McGowan, Sheena; Porter, Corrine J; Lowther, Jonathan; Stack, Colin M; Golding, Sarah J; Skinner-Adams, Tina S; Trenholme, Katharine R; Teuscher, Franka; Donnelly, Sheila M; Grembecka, Jolanta; Mucha, Artur; Kafarski, Pawel; Degori, Ross; Buckle, Ashley M; Gardiner, Donald L; Whisstock, James C; Dalton, John P

    2009-02-24

    Plasmodium falciparum parasites are responsible for the major global disease malaria, which results in >2 million deaths each year. With the rise of drug-resistant malarial parasites, novel drug targets and lead compounds are urgently required for the development of new therapeutic strategies. Here, we address this important problem by targeting the malarial neutral aminopeptidases that are involved in the terminal stages of hemoglobin digestion and essential for the provision of amino acids used for parasite growth and development within the erythrocyte. We characterize the structure and substrate specificity of one such aminopeptidase, PfA-M1, a validated drug target. The X-ray crystal structure of PfA-M1 alone and in complex with the generic inhibitor, bestatin, and a phosphinate dipeptide analogue with potent in vitro and in vivo antimalarial activity, hPheP[CH(2)]Phe, reveals features within the protease active site that are critical to its function as an aminopeptidase and can be exploited for drug development. These results set the groundwork for the development of antimalarial therapeutics that target the neutral aminopeptidases of the parasite.

  13. Determination of aflatoxin M1 levels in Iranian white and cream cheese.

    Science.gov (United States)

    Fallah, Aziz A; Jafari, Tina; Fallah, Ali; Rahnama, Mohammad

    2009-08-01

    A screening survey on the occurrence of aflatoxin M1 (AFM1) was accomplished on 210 cheese samples composed of white cheese (116 samples) and cream cheese (94 samples) purchased from popular markets in central part of Iran (Esfahan and Yazd provinces). The quantitative analysis of AFM1 levels in the samples was performed by using the competitive enzyme-linked immunosorbent assay (ELISA) technique. Aflatoxin M1 at measurable level (50 ng/kg) was detected in 161 (76.6%) samples, consisting of 93 (80.1%) white and 68 (72.3%) cream cheese samples. The concentration of AFM1 in the samples ranged from 52.1 to 785.4 ng/kg. Comparing to legal regulation (250 ng/kg) accepted by some of the countries, 24.2% of the samples exceeded the accepted limit. Among these, the AFM1 levels in 28.4% of white and 19.1% of cream cheese samples were not in accordance with the safety limit. The results indicated that contamination of the samples with AFM1 in such a level appear to be a potential hazard for public health. This paper represents the data of the first survey on the occurrence of AFM1 in cheeses consumed in central part of Iran.

  14. Pirenzepine Promotes the Dimerization of Muscarinic M1 Receptors through a Three-step Binding Process*

    Science.gov (United States)

    Ilien, Brigitte; Glasser, Nicole; Clamme, Jean-Pierre; Didier, Pascal; Piemont, Etienne; Chinnappan, Raja; Daval, Sandrine B.; Galzi, Jean-Luc; Mely, Yves

    2009-01-01

    Ligand binding to G protein-coupled receptors is a complex process that involves sequential receptor conformational changes, ligand translocation, and possibly ligand-induced receptor oligomerization. Binding events at muscarinic acetylcholine receptors are usually interpreted from radioligand binding studies in terms of two-step ligand-induced receptor isomerization. We report here, using a combination of fluorescence approaches, on the molecular mechanisms for Bodipy-pirenzepine binding to enhanced green fluorescent protein (EGFP)-fused muscarinic M1 receptors in living cells. Real time monitoring, under steady-state conditions, of the strong fluorescence energy transfer signal elicited by this interaction permitted a fine kinetic description of the binding process. Time-resolved fluorescence measurements allowed us to identify discrete EGFP lifetime species and to follow their redistribution upon ligand binding. Fluorescence correlation spectroscopy, with EGFP brightness analysis, showed that EGFP-fused muscarinic M1 receptors predominate as monomers in the absence of ligand and dimerize upon pirenzepine binding. Finally, all these experimental data could be quantitatively reconciled into a three-step mechanism, with four identified receptor conformational states. Fast ligand binding to a peripheral receptor site initiates a sequence of conformational changes that allows the ligand to access to inner regions of the protein and drives ligand-receptor complexes toward a high affinity dimeric state. PMID:19451648

  15. Fluorescent pirenzepine derivatives as potential bitopic ligands of the human M1 muscarinic receptor.

    Science.gov (United States)

    Tahtaoui, Chouaib; Parrot, Isabelle; Klotz, Philippe; Guillier, Fabrice; Galzi, Jean-Luc; Hibert, Marcel; Ilien, Brigitte

    2004-08-12

    Following a recent description of fluorescence resonance energy transfer between enhanced green fluorescent protein (EGFP)-fused human muscarinic M1 receptors and Bodipy-labeled pirenzepine, we synthesized seven fluorescent derivatives of this antagonist in order to further characterize ligand-receptor interactions. These compounds carry Bodipy [558/568], Rhodamine Red-X [560/580], or Fluorolink Cy3 [550/570] fluorophores connected to pirenzepine through various linkers. All molecules reversibly bind with high affinity to M1 receptors (radioligand and energy transfer binding experiments) provided that the linker contains more than six atoms. The energy transfer efficiency exhibits modest variations among ligands, indicating that the distance separating EGFP from the fluorophores remains almost constant. This also supports the notion that the fluorophores may bind to the receptor protein. Kinetic analyses reveal that the dissociation of two Bodipy derivatives (10 or 12 atom long linkers) is sensitive to the presence of the allosteric modulator brucine, while that of all other molecules (15-24 atom long linkers) is not. The data favor the idea that these analogues might interact with both the acetylcholine and the brucine binding domains. Copyright 2004 American Chemical Society

  16. Pirenzepine promotes the dimerization of muscarinic M1 receptors through a three-step binding process.

    Science.gov (United States)

    Ilien, Brigitte; Glasser, Nicole; Clamme, Jean-Pierre; Didier, Pascal; Piemont, Etienne; Chinnappan, Raja; Daval, Sandrine B; Galzi, Jean-Luc; Mely, Yves

    2009-07-17

    Ligand binding to G protein-coupled receptors is a complex process that involves sequential receptor conformational changes, ligand translocation, and possibly ligand-induced receptor oligomerization. Binding events at muscarinic acetylcholine receptors are usually interpreted from radioligand binding studies in terms of two-step ligand-induced receptor isomerization. We report here, using a combination of fluorescence approaches, on the molecular mechanisms for Bodipy-pirenzepine binding to enhanced green fluorescent protein (EGFP)-fused muscarinic M1 receptors in living cells. Real time monitoring, under steady-state conditions, of the strong fluorescence energy transfer signal elicited by this interaction permitted a fine kinetic description of the binding process. Time-resolved fluorescence measurements allowed us to identify discrete EGFP lifetime species and to follow their redistribution upon ligand binding. Fluorescence correlation spectroscopy, with EGFP brightness analysis, showed that EGFP-fused muscarinic M1 receptors predominate as monomers in the absence of ligand and dimerize upon pirenzepine binding. Finally, all these experimental data could be quantitatively reconciled into a three-step mechanism, with four identified receptor conformational states. Fast ligand binding to a peripheral receptor site initiates a sequence of conformational changes that allows the ligand to access to inner regions of the protein and drives ligand-receptor complexes toward a high affinity dimeric state.

  17. Molecular Probes for Muscarinic Receptors: Derivatives of the M1-Antagonist Telenzepine

    Science.gov (United States)

    Karton, Yishai; Baumgold, Jesse; Handen, Jeffrey S.; Jacobson, Kenneth A.

    2012-01-01

    Functionalized congeners of the M1-selective muscarinic antagonist telenzepine (4,9-dihydro-3-methyl-4-[(4-methyl-1-piperazinyl)acetyl]-10H-thieno[3,4–b][1,5]benzodiazepin-10-one) were developed and found to bind to the receptor with affinities (Ki values) in approximately the nanomolar range. The derivatives contain a 10-aminodecyl group, which provides a nucleophilic functionality for further derivatization. The attachment of a spacer chain to the distal piperazinyl nitrogen was based on previous findings of enhanced affinity at muscarinic receptors in an analogous series of alkylamino derivatives of pirenzepine [J. Med. Chem. (1991) 34, 2133–2145]. The telenzepine derivatives contain prosthetic groups for radioiodination, protein cross-linking, photoaffinity labeling, and fluorescent labeling and biotin for avidin complexation. The affinity for muscarinic receptors in rat forebrain (mainly m1 subtype) was determined in competitive binding assays vs [3H]-N-methylscopolamine. A (p-aminophenyl)-acetyl derivative for photoaffinity labeling had a Ki value of 0.29 nM at forebrain muscarinic receptors (16-fold higher affinity than telenzepine). A biotin conjugate displayed a Ki value of 0.60 nM at m2-receptors and a 5-fold selectivity versus forebrain. The high affinity of these derivatives makes them suitable for the characterization of muscarinic receptors in pharmacological and spectroscopic studies, for peptide mapping, and for histochemical studies. PMID:1520727

  18. Process economics and safety considerations for the oxidative dehydrogenation of ethane using the M1 catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Baroi, Chinmoy; Gaffney, Anne M.; Fushimi, Rebecca

    2017-05-01

    Olefins or unsaturated hydrocarbons play a vital role as feedstock for many industrially significant processes. Ethylene is the simplest olefin and a key raw material for consumer products. Oxidative Dehydrogenation (ODH) is one of the most promising new routes for ethylene production that can offer a significant advantage in energy efficiency over the conventional steam pyrolysis process. This study is focused on the ODH chemistry using the mixed metal oxide MoVTeNbOx catalysts, generally referred to as M1 for the key phase known to be active for dehydrogenation. Using performance results from the patent literature a series of process simulations were conducted to evaluate the effect of feed composition on operating costs, profitability and process safety. The key results of this study indicate that the ODH reaction can be made safer and more profitable without use of an inert diluent and furthermore by replacing O2 with CO2 as an oxidant. Modifications of the M1 catalyst composition in order to adopt these changes are discussed.

  19. Microscopic description of low-lying M1 excitations in odd-mass actinide nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Tabar, Emre, E-mail: etabar@sakarya.edu.tr [Physics Department, Sakarya University, 54187 Sakarya (Turkey); Biomedical, Magnetic and Semiconductor Materials Research Center (BIMAS-RC), Sakarya University, 54187 Sakarya (Turkey); Yakut, Hakan, E-mail: hyakut@sakarya.edu.tr [Physics Department, Sakarya University, 54187 Sakarya (Turkey); Biomedical, Magnetic and Semiconductor Materials Research Center (BIMAS-RC), Sakarya University, 54187 Sakarya (Turkey); Kuliev, Ali Akbar [Azerbaijan National Academy of Aviation, Baku (Azerbaijan)

    2017-01-15

    A restoration method of a broken symmetry which allows self-consistent determination of the separable effective restoration forces is now adapted to odd-mass nuclei in order to restore violated rotational invariance (RI-) of the Quasiparticle Phonon Nuclear Model (QPNM) Hamiltonian. Because of the self-consistency of the method, these effective forces contain no arbitrary parameters. Within RI-QPNM, the properties of the low-lying magnetic dipole excitations in odd-mass deformed {sup 229–233}Th and {sup 233–239}U nuclei have been investigated for the first time. It has been shown that computed fragmentation of the M1 strengths below 4 MeV in these nuclei is much stronger than that in neighboring doubly even {sup 228–232}Th and {sup 232–238}U nuclei. For {sup 235}U the summed M1 strength in the energy range 1.5–2.8 MeV is in agreement with the relevant experimental data where the missing strength was extracted by means of a fluctuation analysis.

  20. Quadrupole decay strength of the M1 scissors mode of {sup 156}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Beck, T.; Beller, J.; Gayer, U.; Mertes, L.; Pai, H.; Pietralla, N.; Ries, P.; Romig, C.; Werner, V.; Zweidinger, M. [IKP, TU Darmstadt (Germany); Derya, V. [IKP, Universitaet zu Koeln (Germany); Isaak, J.; Loeher, B.; Savran, D. [EMMI, GSI, Darmstadt (Germany); FIAS, Frankfurt (Germany); Scheck, M. [IKP, TU Darmstadt (Germany); School of Engineering, UWS, Paisley (United Kingdom); SUPA, Glasgow (United Kingdom); Tornow, W.; Weller, H.R. [Duke University, Durham (United States)

    2015-07-01

    The isovector low-lying J{sup π}{sub K}=1{sup +}{sub 1} scissors mode of deformed nuclei has been studied extensively in (e,e{sup '}) and (γ,γ{sup '}) experiments over the last 30 years with the main focus on strong M1 transitions to the ground state band. In the framework of the semiclassical two-rotor-model it has its origin in quadrupole deformation. A considerable E2 matrix element between the rotational band of the scissors mode and the ground band is predicted which has not been addressed experimentally. A photon-scattering experiment with linearly-polarized quasi monoenergetic vector (γ)-rays has been performed at the High Intensity vector (γ)-ray Source (HIvector (γ)S) at Duke University, Durham, NC, exploiting the γ{sup 3} setup. We have measured an E2/M1-multipole mixing ratio for the 1{sup +}{sub sc}→2{sup +}{sub 1} transition for the first time. The Alaga rule is applicable and delivers a first estimate of the transition strength B(E2:2{sup +}{sub sc}→0{sup +}{sub 1}). A candidate for a 2{sup +}{sub sc}→2{sup +}{sub 1} transition is discussed.

  1. The Truth-Telling Motor Cortex: Response Competition in M1 Discloses Deceptive Behaviour

    Directory of Open Access Journals (Sweden)

    Aviad A. Hadar

    2011-05-01

    Full Text Available Recent studies have suggested that circuits associated with response conflict and response inhibition are strongly implicated in deception. Using single-pulse transcranial magnetic stimulation (TMS, we examined whether conflict between competing responses in primary motor cortex (M1 can be used for discriminating between intentionally false and true facial recognition. Participants used little finger and thumb key-presses to lie or tell the truth regarding their familiarity with a series of famous and nonfamous faces. Single-pulse TMS was administered to M1 at three intervals prior to response execution in order to evoke motor evoked potentials (MEPs in both Abductor Digiti Minimi (ADM and first dorsal interosseous (FDI of the right hand. As predicted, we found that the MEP of the nonresponding digit was greater than the MEP of the responding digit when participants prepared to engage in deception, while a mirror-reversed pattern was observed for truth telling. This effect did not interact with the stimulation interval suggesting consistent activation of the motor plan representing the truth throughout the response preparation process. We discuss these results with reference to models of response selection and procedures for the detection of deception.

  2. Microscopic description of low-lying M1 excitations in odd-mass actinide nuclei

    Science.gov (United States)

    Tabar, Emre; Yakut, Hakan; Kuliev, Ali Akbar

    2017-01-01

    A restoration method of a broken symmetry which allows self-consistent determination of the separable effective restoration forces is now adapted to odd-mass nuclei in order to restore violated rotational invariance (RI-) of the Quasiparticle Phonon Nuclear Model (QPNM) Hamiltonian. Because of the self-consistency of the method, these effective forces contain no arbitrary parameters. Within RI-QPNM, the properties of the low-lying magnetic dipole excitations in odd-mass deformed 229-233Th and 233-239U nuclei have been investigated for the first time. It has been shown that computed fragmentation of the M1 strengths below 4 MeV in these nuclei is much stronger than that in neighboring doubly even 228-232Th and 232-238U nuclei. For 235U the summed M1 strength in the energy range 1.5-2.8 MeV is in agreement with the relevant experimental data where the missing strength was extracted by means of a fluctuation analysis.

  3. Carboxyl- and amino-functionalized polystyrene nanoparticles differentially affect the polarization profile of M1 and M2 macrophage subsets.

    Science.gov (United States)

    Fuchs, Ann-Kathrin; Syrovets, Tatiana; Haas, Karina A; Loos, Cornelia; Musyanovych, Anna; Mailänder, Volker; Landfester, Katharina; Simmet, Thomas

    2016-04-01

    Macrophages are key regulators of innate and adaptive immune responses. Exposure to microenvironmental stimuli determines their polarization into proinflammatory M1 and anti-inflammatory M2 macrophages. M1 exhibit high expression of proinflammatory TNF-α and IL-1β, and M2 promote tissue repair, but likewise support tumor growth and cause immune suppression by expressing IL-10. Thus, the M1/M2 balance critically determines tissue homeostasis. By using carboxyl- (PS-COOH) and amino-functionalized (PS-NH2) polystyrene nanoparticles, the effects of surface decoration on the polarization of human macrophages were investigated. The nanoparticles did not compromise macrophage viability nor did they affect the expression of the M1 markers CD86, NOS2, TNF-α, and IL-1β. By contrast, in M2, both nanoparticles impaired expression of scavenger receptor CD163 and CD200R, and the release of IL-10. PS-NH2 also inhibited phagocytosis of Escherichia coli by both, M1 and M2. PS-COOH did not impair phagocytosis by M2, but increased protein mass in M1 and M2, TGF-β1 release by M1, and ATP levels in M2. Thus, nanoparticles skew the M2 macrophage polarization without affecting M1 markers. Given the critical role of the M1 and M2 polarization for the immunological balance in patients with cancer or chronic inflammation, functionalized nanoparticles might serve as tools for reprogramming the M1/M2 polarization.

  4. Effect of particle volume fraction on the settling velocity of volcanic ash particles: implications for ash dispersion models

    Science.gov (United States)

    Del Bello, E.; Taddeucci, J.; De'Michieli Vitturi, M.; Scarlato, P.; Andronico, D.; Scollo, S.; Kueppers, U.

    2015-12-01

    We present the first report of experimental measurements of the enhanced settling velocity of volcanic particles as function of particle volume fraction. In order to investigate the differences in the aerodynamic behavior of ash particles when settling individually or in mass, we performed systematic large-scale ash settling experiments using natural basaltic and phonolitic ash. By releasing ash particles at different, controlled volumetric flow rates, in an unconstrained open space and at minimal air movement, we measured their terminal velocity, size, and particle volume fraction with a high-speed camera at 2000 fps. Enhanced settling velocities of individual particles increase with increasing particle volume fraction. This suggests that particle clustering during fallout may be one reason explaining larger than theoretical depletion rates of fine particles from volcanic ash clouds. We provide a quantitative empirical model that allows to calculate, from a given particle size and density, the enhanced velocity resulting from a given particle volume fraction. The proposed model has the potential to serve as a simple tool for the prediction of the terminal velocity of ash of an hypothetical distribution of ash of known particle size and volume fraction. This is of particular importance for advection-diffusion transport model of ash where generally a one-way coupling is adopted, considering only the flow effects on particles. To better quantify the importance of the enhanced settling velocity in ash dispersal, we finally introduced the new formulation in a Lagrangian model calculating for realistic eruptive conditions the resulting ash concentration in the atmosphere and on the ground.

  5. Involvement of an Arginine Triplet in M1 Matrix Protein Interaction with Membranes and in M1 Recruitment into Virus-Like Particles of the Influenza A(H1N1)pdm09 Virus

    Science.gov (United States)

    Moncorgé, Olivier; Panthu, Baptiste; Prchal, Jan; Décimo, Didier; Ohlmann, Théophile; Lina, Bruno; Favard, Cyril; Decroly, Etienne; Ottmann, Michèle; Roingeard, Philippe; Muriaux, Delphine

    2016-01-01

    The influenza A(H1N1)pdm09 virus caused the first influenza pandemic of the 21st century. In this study, we wanted to decipher the role of conserved basic residues of the viral M1 matrix protein in virus assembly and release. M1 plays many roles in the influenza virus replication cycle. Specifically, it participates in viral particle assembly, can associate with the viral ribonucleoprotein complexes and can bind to the cell plasma membrane and/or the cytoplasmic tail of viral transmembrane proteins. M1 contains an N-terminal domain of 164 amino acids with two basic domains: the nuclear localization signal on helix 6 and an arginine triplet (R76/77/78) on helix 5. To investigate the role of these two M1 basic domains in influenza A(H1N1)pdm09 virus molecular assembly, we analyzed M1 attachment to membranes, virus-like particle (VLP) production and virus infectivity. In vitro, M1 binding to large unilamellar vesicles (LUVs), which contain negatively charged lipids, decreased significantly when the M1 R76/77/78 motif was mutated. In cells, M1 alone was mainly observed in the nucleus (47%) and in the cytosol (42%). Conversely, when co-expressed with the viral proteins NS1/NEP and M2, M1 was relocated to the cell membranes (55%), as shown by subcellular fractionation experiments. This minimal system allowed the production of M1 containing-VLPs. However, M1 with mutations in the arginine triplet accumulated in intracellular clusters and its incorporation in VLPs was strongly diminished. M2 over-expression was essential for M1 membrane localization and VLP production, whereas the viral trans-membrane proteins HA and NA seemed dispensable. These results suggest that the M1 arginine triplet participates in M1 interaction with membranes. This R76/77/78 motif is essential for M1 incorporation in virus particles and the importance of this motif was confirmed by reverse genetic demonstrating that its mutation is lethal for the virus. These results highlight the molecular

  6. Polymorphism of Glutathione S-transferase T1, M1 and P1 Genes in a Shanghai Population: Patients With Occupational or Non-occupational Bladder Cancer

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective Glutathione S-transferases are involved in the conjugation of xenobiotics. To explore whether GSTs polymorphisms are involved in the development of occupational or non-occupational bladder cancer, polymorphism frequencies of GSTT1, M1 and P1 were investigated in a normal population, which had been settled in a rural area in Shanghai suburb for at least 5 generations as well as in a group of patients with benzidine exposure related occupational bladder cancer in Shanghai dyestuff industry and a group of patients with non-occupational bladder cancer. Methods PCR based procedures were performed in the study populations to confirm the genotypes of GSTT1, M1 and P1. Results The polymorphisms at locus of GSTP1- A1578G in the normal population differed significantly from those in Caucasians or African Americans. All the subjects genotyped so far (n =118) bore only homogenous wild genotype (C2293/ C2293) at GSTP1 - C2293T locus. This locus seemed to be a monomorphic in Shanghai population. No significant difference in GSTT1 and GSTM1 polymorphic form frequencies could be confirmed among three groups of subjects. An overrepresentation of GSTP1 AG or GG genotype corresponding a less stable and less effective isozyme protein was detected in patients with benzidine related occupational bladder cancer, compared with that in the normal population though a statistical significance was not yet reached (P=0.09, OR=1.96, 95% CI 0.89-4.32,). Conclusion This study suggests that GSTM1 or GSTT1 homozygous deficiency genotypes and their combination do not have a clear impact on bladder cancer incidence in a Shanghai population. It seems that GSTP1 polymorphism is not associated with non-occupational bladder cancer. GSTP1 AG or GG genotype has a higher frequency in the patients with benzidine related occupational bladder cancer, and further work is needed to confirm if GSTP1 AG or GG genotype plays a role in the development of occupational bladder cancer.

  7. Settling of Spinel in a High-Level Waste Glass Melter

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R.; Schill, Pert; Nemec, Lubomir

    2002-01-18

    High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors called melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a temperature as high as 1150?C (or even higher in advanced melters) to create a melt that becomes glass on cooling. This process is slow and expensive. Moreover, the melters that are currently in use or are going to be used in the U.S. are sensitive to clogging and thus cannot process melt in which solid particles are suspended. These particles settle and gradually accumulate on the melter bottom. Such particles, most often small crystals of spinel (a mineral containing iron, nickel, chromium, and other minor oxides), inevitably occur in the melt when the content of the waste in the glass (called waste loading) increases above a certain limit. To avoid the presence of solid particles in the melter, the waste loading is kept rather low, in average 15% lower than in glass formulated for more robust melters.

  8. Settling of Spinel in A High-Level Waste Glass Melter

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Hrma; Pert Schill; Lubomir Nemec

    2002-01-07

    High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors call melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a temperature as high as 1150 degree C (or even higher in advanced melters) to create a melt that becomes glass on cooling. This process is slow and expensive. Moreover, the melters that are currently in use or are going to be used in the U.S. are sensitive to clogging and thus cannot process melt in which solid particles are suspended. These particles settle and gradually accumulate on the melter bottom. Such particles, most often small crystals of spinel ( a mineral containing iron, nickel, chromium, and other minor oxides), inevitably occurred in the melt when the content of the waste in the glass (called waste loading) increases above a certain limit. To avoid the presence of solid particles in the melter, the waste loading is kept rather low, in average 15% lower than in glass formulated for more robust melters.

  9. Microbial community in anoxic-oxic-settling-anaerobic sludge reduction process revealed by 454 pyrosequencing analysis.

    Science.gov (United States)

    Ning, Xinqiang; Qiao, Wenwen; Zhang, Lei; Gao, Xu

    2014-12-01

    Modification of the anoxic-oxic (AO) process by inserting a sludge holding tank (SHT) into the sludge return line forms an anoxic-oxic-settling-anaerobic (A+OSA) process that can achieve a 48.98% sludge reduction rate. The 454 pyrosequencing method was used to obtain the microbial communities of the AO and A+OSA processes. Results showed that the microbial community structures of the 2 processes were different as a result of the SHT insertion. Bacteria assigned to the phyla Proteobacteria and Bacteroidetes commonly existed and dominated the microbial populations of the 2 processes. However, the relative abundance of these populations shifted in the presence of SHT. The relative abundance of Proteobacteria decreased during the A+OSA process. A specific comparison at the class level showed that Sphingobacteria was enriched in the A+OSA process. The result suggested that the fermentative bacteria Sphingobacteria may have key functions in reducing the sludge from the A+OSA process. Uncultured Nitrosomonadaceae gradually became the dominant ammonia-oxidizing bacteria, and the nitrite-oxidizing bacterium Nitrospira was enriched in the A+OSA process. Both occurrences were favorable for stabilized nitrogen removal. The known denitrifying species in the A+OSA process were similar to those in the AO process; however, their relative abundance also decreased.

  10. Coal-tar-based parking lot sealcoat: An unrecognized source of PAH to settled house dust

    Science.gov (United States)

    Mahler, B.J.; Van Metre, P.C.; Wilson, J.T.; Musgrove, M.; Burbank, T.L.; Ennis, T.E.; Bashara, T.J.

    2010-01-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coaltar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 ??g/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 ??g/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 ??g/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 ??g/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant. ?? 2010 American Chemical Society.

  11. Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area

    Directory of Open Access Journals (Sweden)

    Dejun Wan

    2016-05-01

    Full Text Available To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10−6–10−4 but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75% by As, Pb, and Sb, and dominantly (92% via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust.

  12. Influence of the winter phytoplankton bloom on the settled material in a temperate shallow estuary

    Directory of Open Access Journals (Sweden)

    Valeria A. Guinder

    2015-01-01

    Full Text Available The development of the phytoplankton winter bloom and the accumulation of particulate suspended matter (PSM inside sediment collectors were assessed in the inner zone of the Bahía Blanca Estuary. The phytoplankton bloom (chlorophyll up to 25 μg l−1 and abundance up to 8 × 106 cells l−1 was related with high levels of dissolved inorganic nutrients and underwater light availability (Im up to 355 μE m−2 s−1 and was dominated by relatively small diatoms, e.g. Chaetoceros sp.1 (3–8 μm. Conversely, large planktonic diatoms, mostly Thalassiosira spp. 20–60 μm, were found in the accumulated material inside the collectors, together with benthic microalgae and high concentrations of chlorophyll, phaeopigments, particulate organic matter (POM between 18 and 32% of total PSM and C:N ratios >12. The composition of the settled material indicated vertical exportation of phytoplankton to the benthos, external loads of detritus and bottom resuspension. The present study highlights the close benthic‐pelagic interactions in shallow coastal environments characterized by high productivity.

  13. Model of the hydrodynamic loads applied on a rotating halfbridge belonging to a circular settling tank

    Science.gov (United States)

    Dascalescu, A. E.; Lazaroiu, G.; Scupi, A. A.; Oanta, E.

    2016-08-01

    The rotating half-bridge of a settling tank is employed to sweep the sludge from the wastewater and to vacuum and sent it to the central collector. It has a complex geometry but the main beam may be considered a slender bar loaded by the following category of forces: concentrated forces produced by the weight of the scrapping system of blades, suction pipes, local sludge collecting chamber, plus the sludge in the horizontal sludge transporting pipes; forces produced by the access bridge; buoyant forces produced by the floating barrels according to Archimedes’ principle; distributed forces produced by the weight of the main bridge; hydrodynamic forces. In order to evaluate the hydrodynamic loads we have conceived a numerical model based on the finite volume method, using the ANSYS-Fluent software. To model the flow we used the equations of Reynolds Averaged Navier-Stokes (RANS) for liquids together with Volume of Fluid model (VOF) for multiphase flows. For turbulent model k-epsilon we used the equation for turbulent kinetic energy k and dissipation epsilon. These results will be used to increase the accuracy of the loads’ sub-model in the theoretical models, e. the finite element model and the analytical model.

  14. Motion of a Free-Settling Spherical Particle Driven by a Laser-Induced Bubble

    Science.gov (United States)

    Wu, Shengji; Zuo, Zhigang; Stone, Howard A.; Liu, Shuhong

    2017-08-01

    We document experimentally four different interactions of a laser-induced bubble and a free-settling particle, with different combinations of the geometric and physical parameters of the system. Our force balance model shows that four nondimensional factors involving the particle radius a , the maximum bubble radius Rmax , the initial separation distance l0 between the particle center and the bubble center, the fluid viscosity μf , and the particle and fluid densities ρp and ρf , respectively, in detail l0 /Rmax , a /Rmax , ρp /ρf , and μ*=μfTc /ρfRmax2 , where Tc=0.915 Rmax√{ρf /(p∞-pv ) } , influence the particle-bubble dynamics, and reasonably predict the maximum particle velocity and the limiting condition when the particle starts to "bounce off" the bubble during bubble growth. In particular, we also discover the high-speed ejection of the particle, and a cavity behind the particle, in cases when initially the particle is in very close proximity to the bubble. These observations offer new insights into the causal mechanism for the enhanced cavitation erosion in silt-laden water.

  15. Coal-tar-based parking lot sealcoat: an unrecognized source of PAH to settled house dust.

    Science.gov (United States)

    Mahler, Barbara J; Metre, Peter C Van; Wilson, Jennifer T; Musgrove, Marylynn; Burbank, Teresa L; Ennis, Thomas E; Bashara, Thomas J

    2010-02-01

    Despite much speculation, the principal factors controlling concentrations of polycyclic aromatic hydrocarbons (PAH) in settled house dust (SHD) have not yet been identified. In response to recent reports that dust from pavement with coal-tar-based sealcoat contains extremely high concentrations of PAH, we measured PAH in SHD from 23 apartments and in dust from their associated parking lots, one-half of which had coal-tar-based sealcoat (CT). The median concentration of total PAH (T-PAH) in dust from CT parking lots (4760 microg/g, n = 11) was 530 times higher than that from parking lots with other pavement surface types (asphalt-based sealcoat, unsealed asphalt, concrete [median 9.0 microg/g, n = 12]). T-PAH in SHD from apartments with CT parking lots (median 129 microg/g) was 25 times higher than that in SHD from apartments with parking lots with other pavement surface types (median 5.1 microg/g). Presence or absence of CT on a parking lot explained 48% of the variance in log-transformed T-PAH in SHD. Urban land-use intensity near the residence also had a significant but weaker relation to T-PAH. No other variables tested, including carpeting, frequency of vacuuming, and indoor burning, were significant.

  16. Endotoxin levels in settled airborne dust in European schools: the HITEA school study.

    Science.gov (United States)

    Jacobs, J H; Krop, E J M; Borras-Santos, A; Zock, J-P; Taubel, M; Hyvarinnen, A; Pekkanen, J; Doekes, G; Heederik, D J J

    2014-04-01

    Indoor exposure to microbial agents is known to influence respiratory health. Besides home exposure, exposure in schools can affect respiratory health. In this study, we measured endotoxin in settled dust in primary schools in three European countries from three different geographical regions with different climates. Our aim was to characterize endotoxin levels in primary schools and evaluate associations with potential determinants. Endotoxin levels were repeatedly assessed in 23 schools in Spain (n = 7), the Netherlands (n = 10), and Finland (n = 6) using electrostatic dustfall collectors. In total, 645 measurements were taken in 237 classrooms. Endotoxin levels differed significantly between countries; Dutch schools had the highest levels, while Finnish schools showed the lowest levels. In each country, differences in endotoxin levels were observed between schools and over the sampling periods. Estimates improved after adjustment for sampling period. Factors affecting endotoxin levels in a school differed per country. In general, endotoxin levels were higher in lower grades and in classrooms with higher occupancy. School endotoxin levels may contribute significantly to total endotoxin exposure in children and teachers. As the correlation between the repeated measurements is reasonable, single endotoxin measurements form a reasonable basis for estimating annual endotoxin levels in schools.

  17. Performance of Africanized honeybee colonies settled by queens selected for different traits

    Directory of Open Access Journals (Sweden)

    Tânia Patrícia Schafaschek

    2016-01-01

    Full Text Available We evaluated varroa infestation and the performance of Africanized honeybee colonies with queens selected for honey and royal jelly production, and also unselected queens, correlating with climatic variables. In Campo Alegre, Santa Catarina State, Brazil, the experiment I used 10 Langstroth hives and in Mafra, Santa Catarina State, Brazil, the experiment II was performed with 15 Schenk hives. A mapping in areas of sealed and unsealed brood, honey and pollen was carried out on days zero, 45 and 90 days after the introduction of the queen. In the experiment I, there was interaction between the type of queen selection and the evaluation period for areas of sealed brood, honey, and total stored food. The group selected for royal jelly production presented larger sealed brood area and smaller honey area at 90 days. Varroa infestation was lower (p < 0.05 at 90 days. The type of queen selection and the evaluation period influenced the sealed brood area, the total brood and the total area occupied in the colony. The high relative humidity caused greater honey storage for the local group. The different groups of queens presented different behavior according to the environment in which they are settled.

  18. Dynamic one-dimensional modeling of secondary settling tanks and design impacts of sizing decisions.

    Science.gov (United States)

    Li, Ben; Stenstrom, Michael K

    2014-03-01

    As one of the most significant components in the activated sludge process (ASP), secondary settling tanks (SSTs) can be investigated with mathematical models to optimize design and operation. This paper takes a new look at the one-dimensional (1-D) SST model by analyzing and considering the impacts of numerical problems, especially the process robustness. An improved SST model with Yee-Roe-Davis technique as the PDE solver is proposed and compared with the widely used Takács model to show its improvement in numerical solution quality. The improved and Takács models are coupled with a bioreactor model to reevaluate ASP design basis and several popular control strategies for economic plausibility, contaminant removal efficiency and system robustness. The time-to-failure due to rising sludge blanket during overloading, as a key robustness indicator, is analyzed to demonstrate the differences caused by numerical issues in SST models. The calculated results indicate that the Takács model significantly underestimates time to failure, thus leading to a conservative design.

  19. Photovoltaic System Regulation Based on a PID Fuzzy Controller to Ensure a Fixed Settling Time

    Directory of Open Access Journals (Sweden)

    Paula A. Ortiz-Valencia

    2013-11-01

    Full Text Available The main objective of the controllers in photovoltaic systems (PV is to ensure the maximum extraction of the available power. Those controllers usually combine the action of a maximum power point tracking algorithm (MPPT with a voltage regulator, which has the function of rejecting disturbances at the panel terminals. Such controllers are commonly based on PI and PID structures, it requiring linearized models at an operating point. But, due to disturbances generated by the environment and the load, the operating point of the system changes drastically, which hinder to obtain the desired system performance. This paper proposes to regulate the PV system using a Fuzzy PID controller, which adapts to changes in solar irradiance and load oscillations. This characteristic guarantees a constant settling time, which is required to precisely define the period of the MPPT algorithm. In the case of classical linear controllers, the period of the MPPT algorithm is set to the worst case (longest period which generates additional power losses by slowing down the tracking of the optimal operating point. Therefore, the solution proposed in this paper improves the overall system efficiency. Finally, such a solution is validated through simulations in Matlab®.

  20. Partitioning tungsten between matrix precursors and chondrule precursors through relative settling

    CERN Document Server

    Hubbard, Alexander

    2016-01-01

    Recent studies of chondrites have found a tungsten isotopic anomaly between chondrules and matrix. Given the refractory nature of tungsten, this implies that W was carried into the solar nebula by at least two distinct families of pre-solar grains. The observed chondrule/matrix split requires that the distinct families were kept separate during the dust coagulation process, and that the two families of grain interacted with the chondrule formation mechanism differently. We take the co-existence of different families of solids in the same general orbital region at the chondrule-precursor size as given, and explore the requirements for them to have interacted with the chondrule formation process at significantly different rates. We show that this sorting of families of solids into chondrule and matrix destined dust had to have been at least as powerful a sorting mechanism as the relative settling of aerodynamically distinct grains at at least two scale heights above the midplane. The requirement that the chondr...

  1. The human Müller cell line MIO-M1 expresses opsins.

    Science.gov (United States)

    Hollborn, Margrit; Ulbricht, Elke; Rillich, Katja; Dukic-Stefanovic, Sladjana; Wurm, Antje; Wagner, Lysann; Reichenbach, Andreas; Wiedemann, Peter; Limb, Gloria Astrid; Bringmann, Andreas; Kohen, Leon

    2011-01-01

    To determine whether the human Müller cell line Moorfields/Institute of Ophthalmology-Müller 1 (MIO-M1) expresses opsins. The gene expression of opsins was determined by reverse-transcription PCR (RT-PCR). The presence of opsin proteins was determined by western blotting and immunocytochemistry. The light sensitivity of the cells was examined with imaging experiments using the calcium-sensitive dye Fluo-4. MIO-M1 cells express glial (glutamine synthase [GLUL], vimentin [VIM], glial fibrillary acidic protein [GFAP], cellular retinaldehyde-binding protein [RLBP1], glial high-affinity glutamate transporter [SLCA1], aquaporin-4 [AQP4], inwardly rectifying potassium channel Kir4.1 [Kir4.1]), neuronal (Thy-1 cell surface antigen [THY1], heavy neurofilament polypeptide [NEFH], microtubule-associated protein 2 [MAP2], neurogenic differentiation 1 [NEUROD1], neuronal nuclei [NEUN]), and neural progenitor markers (Nestin [NES], paired-type homeobox transcription factor [PAX6], neurogenic locus notch homolog 1 [NOTCH1]). The cells contain mRNA for the following opsins: blue opsin (OPN1SW), rhodopsin (OPN2), panopsin (OPN3), melanopsin (OPN4), neuropsin (OPN5), and peropsin (RRH), as well as for the transducins (guanine nucleotide binding protein [GNAZ], alpha transducing activity polypeptide 1 [GNAT1], alpha transducing activity polypeptide 2 [GNAT2]). The presence of blue opsin and melanopsin was confirmed with immunocytochemistry and western blotting. The immunoreactivity and mRNA of red-green opsin were found in some but not all cultures, while the immunoreactivity for rhodopsin was absent in all cultures investigated. Repetitive stimulation with 480 nm light evoked slow and fast transient calcium responses in the majority of cells investigated, while irradiation with 600 nm light was ineffective. The human Müller cell line MIO-M1 expresses opsins. This suggests immortalized Müller cells could be used as a cellular source to produce human opsins for their potential

  2. State-dependent and timing-dependent bidirectional associative plasticity in the human SMA-M1 network.

    Science.gov (United States)

    Arai, Noritoshi; Müller-Dahlhaus, Florian; Murakami, Takenobu; Bliem, Barbara; Lu, Ming-Kuei; Ugawa, Yoshikazu; Ziemann, Ulf

    2011-10-26

    The supplementary motor area (SMA-proper) plays a key role in the preparation and execution of voluntary movements. Anatomically, SMA-proper is densely reciprocally connected to primary motor cortex (M1), but neuronal coordination within the SMA-M1 network and its modification by external perturbation are not well understood. Here we modulated the SMA-M1 network using MR-navigated multicoil associative transcranial magnetic stimulation in healthy subjects. Changes in corticospinal excitability were assessed by recording motor evoked potential (MEP) amplitude bilaterally in a hand muscle. We found timing-dependent bidirectional Hebbian-like MEP changes during and for at least 30 min after paired associative SMA-M1 stimulation. MEP amplitude increased if SMA stimulation preceded M1 stimulation by 6 ms, but decreased if SMA stimulation lagged M1 stimulation by 15 ms. This associative plasticity in the SMA-M1 network was highly topographically specific because paired associative stimulation of pre-SMA and M1 did not result in any significant MEP change. Furthermore, associative plasticity in the SMA-M1 network was strongly state-dependent because it required priming by near-simultaneous M1 stimulation to occur. We conclude that timing-dependent bidirectional associative plasticity is demonstrated for the first time at the systems level of a human corticocortical neuronal network. The properties of this form of plasticity are fully compatible with spike-timing-dependent plasticity as defined at the cellular level. The necessity of priming may reflect the strong interhemispheric connectivity of the SMA-M1 network. Findings are relevant for better understanding reorganization and potentially therapeutic modification of neuronal coordination in the SMA-M1 network after cerebral lesions such as stroke.

  3. Irreducible Modular Representations of the Reflection Group G(m,1,n

    Directory of Open Access Journals (Sweden)

    José O. Araujo

    2015-01-01

    Full Text Available In an article published in 1980, Farahat and Peel realized the irreducible modular representations of the symmetric group. One year later, Al-Aamily, Morris, and Peel constructed the irreducible modular representations for a Weyl group of type Bn. In both cases, combinatorial methods were used. Almost twenty years later, using a geometric construction based on the ideas of Macdonald, first Aguado and Araujo and then Araujo, Bigeón, and Gamondi also realized the irreducible modular representations for the Weyl groups of types An and Bn. In this paper, we extend the geometric construction based on the ideas of Macdonald to realize the irreducible modular representations of the complex reflection group of type G(m,1,n.

  4. E2 and M1 Transition Probabilities in Odd Mass Hg Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Berg, V.; Baecklin, A.; Fogelberg, B.; Malmskog, S.G.

    1969-10-15

    L- and M-subshell ratios have been measured for the 39.5 keV transition in {sup 193}Hg and the 37.1 and 16.2 keV transitions in {sup 195}Hg yielding 0.38 {+-} 0.12 , <0.02 and 0.08 {+-} 0.03 per cent E2, respectively. The half-lives of the 39.5 keV level in {sup 193}Hg and the 53.3 and 37.1 keV levels in {sup 195}Hg have been measured by the delayed coincidence method, yielding values of 0.63 {+-} 0.03, 0.72 {+-} 0.03 and <0.05 nsec respectively. A systematic compilation of reduced E2 and M1 transition probabilities in odd mass Pt, Hg and Pb nuclei is given and compared to theoretical predictions.

  5. Occurrence of aflatoxin M(1) in dairy products in southern Italy.

    Science.gov (United States)

    Montagna, Maria Teresa; Napoli, Christian; De Giglio, Osvalda; Iatta, Roberta; Barbuti, Giovanna

    2008-12-01

    A screening survey of the presence of aflatoxin M(1) (AFM(1)) was carried out on 265 samples of cheese made from cow, buffalo, goat, sheep, sheep-goat milk collected in the Apulia region (Southern Italy). Selected samples included unripened, medium and long-term ripened cheeses. AFM(1) was found in 16.6% of the analyzed samples. The highest positive incidence was for medium and long-term ripened cheeses, especially those made from sheep-goat milk, while buffalo cheeses tested consistently negative. Our results show that the level of contamination by AFM(1) in dairy products from Apulia Region are lower than in other Italian and European regions. Moreover, it is important to underline that a common European norm concerning the AFM(1) threshold limits for dairy products is still lacking.

  6. Excretion of Aflatoxin M1 in milk of goats fed diet contaminated by Aflatoxin B1

    Directory of Open Access Journals (Sweden)

    Gianni Battacone

    2010-01-01

    Full Text Available An experiment was carried out to study the excretion of aflatoxin M1(AFM1 in milk of three goats fed a single dose (0.8mg/head of pure aflatoxin B1 (AFB1. The values of AFM1 concentration excreted in milk was highly variable among goats, even if the pattern of excretion over time was very similar among the three animals. AFM1 was first detected at the milking performed 1h after the AFB1 administration. The highest values of AFM1 concentration in milk were reached 3 and 6h after the AFB1 intake. The trend of clearance of AFM1 in milk over time was expressed by a decreasing exponential equation. AFM1 concentration was below the EU maximum allowed level (50 ng/L in milk collected 36 h after the AFB1 administration.

  7. Robinson-Schensted-Knuth Correspondence and Weak Polynomial Identities of M1,1(E)

    Institute of Scientific and Technical Information of China (English)

    Onofrio Mario Di Vincenzo; Roberto La Scala

    2005-01-01

    In this paper, it is proved that the ideal Iω of the weak polynomial identities of the superalgebra M1,1(E) is generated by the p roper polynomials [x1,x2, x3] and [x2,x1][xa,x1][x4, x1]. This is proved for any infinite field F of characteristic different a basis and the dimension of any multihomogeneous component of the quotient algebra B/(B ∩ Iw). We also compute the Hilbert series of this algebra. One of the main tools of this paper is a variant we found of the Robinson-Schensted-Knuth correspondence defined for single semistandard tableaux of double shape.

  8. Solvent affects the conformation of virginiamycin M1 (pristinamycin IIA, streptogramin A).

    Science.gov (United States)

    Dang, Jason; Bergdahl, Mikael; Separovic, Frances; Brownlee, Robert T C; Metzger, Robert P

    2004-10-21

    The streptogramins are antibiotics which act by binding two different components at separate nearby sites on the bacterial 50S ribosome, inhibiting protein synthesis. The first component, a macrolactone, is common to many of the streptogramin antibiotics and, thus, is referred to by many names including virginiamycin M1(VM1), pristinamycin IIA, ostreogrycin A and streptogramin A. X-Ray crystallographic studies of VM1 bound to ribosomes and to a deactivating enzyme show a different conformation to that of VM1 in chloroform solution. We now report the results of high resolution 2D NMR experiments that show that the conformation of VM1 in dimethyl sulfoxide and methanol differs from both that in chloroform solution and in the bound form. The 3D structure and the 1H NMR and 13C NMR chemical shifts of VM1 in dimethyl sulfoxide and methanol are described.

  9. RAPD Analysis of M1 Generation of Gladiolus hybridus Hort Treated by EMS

    Institute of Scientific and Technical Information of China (English)

    WANG Jingang; GUO Ying; CHE Daidi; LIU Shenkui; YANG Chuanpin

    2009-01-01

    Gladiolus hybridus Hort is one of the world's famous cutting flowers. It is very popular because of the big size, bright color, various shape, and long period of bloom. New species should be cultivated in order to meet the consumers' need of asking for the new. Among the technologies of cultivating new species of flowers, mutagenic breeding is a shortcut. This study treated corm bud of G. hybridus Hort with EMS of different consistency. Then M1 after treated was analyzed by RAPD. The result showed that EMS was a very effective mutagenic agent for the corm bud of G. hybridus Hort. With the increase of consistency, the mutagenic range increased first, then decreased, among which 0.6% EMS treatment had the biggest influence. However, with the same EMS consistency, there was not close relevancy between the amount of mutagenic agent and the divergence of plant's genomes, which offered a molecular basis for selecting plants with good mutation.

  10. Occurrence of Aflatoxin M1 in Dairy Products in Southern Italy

    Directory of Open Access Journals (Sweden)

    Giovanna Barbuti

    2008-12-01

    Full Text Available A screening survey of the presence of aflatoxin M1 (AFM1 was carried out on 265 samples of cheese made from cow, buffalo, goat, sheep, sheep-goat milk collected in the Apulia region (Southern Italy. Selected samples included unripened, medium and long-term ripened cheeses. AFM1 was found in 16.6% of the analyzed samples. The highest positive incidence was for medium and long-term ripened cheeses, especially those made from sheep-goat milk, while buffalo cheeses tested consistently negative. Our results show that the level of contamination by AFM1 in dairy products from Apulia Region are lower than in other Italian and European regions. Moreover, it is important to underline that a common European norm concerning the AFM1 threshold limits for dairy products is still lacking.

  11. An Automatic Detection Method of Nanocomposite Film Element Based on GLCM and Adaboost M1

    Directory of Open Access Journals (Sweden)

    Hai Guo

    2015-01-01

    Full Text Available An automatic detection model adopting pattern recognition technology is proposed in this paper; it can realize the measurement to the element of nanocomposite film. The features of gray level cooccurrence matrix (GLCM can be extracted from different types of surface morphology images of film; after that, the dimension reduction of film can be handled by principal component analysis (PCA. So it is possible to identify the element of film according to the Adaboost M1 algorithm of a strong classifier with ten decision tree classifiers. The experimental result shows that this model is superior to the ones of SVM (support vector machine, NN and BayesNet. The method proposed can be widely applied to the automatic detection of not only nanocomposite film element but also other nanocomposite material elements.

  12. The M/M/1 Queue with Controlled Multiple Working Vacations

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-bo; FENG Ping-hua

    2013-01-01

    In this paper,we study an M/M/1 queue with multiple working vacations under following Bernoulli control policy:at the instants of the completion of a service in vacation,the server will interrupt the vacation and enter regular busy period with probabiiity1-p (if there are customers in the queue) or continue the vacation with probability p.For this model,we drive the analytic expression of the stationary queue length and demonstrate stochastic decomposition structures of the stationary queue length and waiting time,also we obtain the additional queue length and the additional delay of this model.The results we got agree with the corresponding results for working vacation model with or without vacation interruption if we set p =0 or p =1,respectively.

  13. Detection of Aflatoxin M1 in Milk from Qom (Aried and Semiaried Province of Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Dakhili

    2016-06-01

    Full Text Available Background: Aflatoxins are secondary metabolites fungal When animals consume contaminated feed stuff to Aflatoxin B1 (AFB1, the toxin hydrolyzed and changed to the aflatoxin M1 and transmit to the milk consumers. Methods: seventy milk samples from different milk producers who were selling their milk to the dairy plant during two season in winter and summer and investigated by Enzyme Linked Immuno Sorbent Assay (ELISA. Results: AFM1 was found in 100% of the milk samples in winter. About 15% of the samples had AFM1 greater than the maximum tolerance limit (50ng/l accepted by European Union. Mean concentrations of AFM1 in Winter, Summer were 122, 53 ng/L, respectively. Mean concentrations of AFM1 in winter and Summer samples were significantly higher (P<0.05. Conclusion: these results show that the important of periodically monitoring the occurrence of AFM1 in raw milk and dairy products in Qom province.

  14. Fluid queues driven by an M/M/1/N queue

    Directory of Open Access Journals (Sweden)

    R. B. Lenin

    2000-01-01

    Full Text Available In this paper, we consider fluid queue models with infinite buffer capacity which receives and releases fluid at variable rates in such a way that the net input rate of fluid into the buffer (which is negative when fluid is flowing out of the buffer is uniquely determined by the number of customers in an M/M/1/N queue model (that is, the fluid queue is driven by this Markovian queue with constant arrival and service rates. We use some interesting identities of tridiagonal determinants to find analytically the eigenvalues of the underlying tridiagonal matrix and hence the distribution function of the buffer occupancy. For specific cases, we verify the results available in the literature.

  15. Scaled-energy spectroscopy of a |M|=1 Rydberg barium atom in an electric field

    Institute of Scientific and Technical Information of China (English)

    Wang Lei; Quan Wei; Shen Li; Yang Hai-Feng; Shi Ting-Yun; Liu Xiao-Jun; Liu Hong-Ping; Zhan Ming-Sheng

    2009-01-01

    We observe strong energy-dependent quantum defects in the scaled-energy Stark spectra for |M|=1 Rydberg states of barium atoms at three scaled energies: ε= -2.000, ε= -2.500 and ε=-3.000. In an attempt to explain the observations, theoretical calculations of closed orbit theory based on a model potential including core effect are performed for non-hydrogenic atoms. While such a potential has been uniformly successful for alkali atoms with a single valence electron, it fails to match experimental results for barium atoms in the 6snp Rydberg states with two valence electrons. Our study points out that this discrepancy is due to the strong perturbation from the 5d8p state, which voids the simple approximation for constant quantum defects of principle quantum number n.

  16. E1M1 and E1E2 transition probabilities in one-electron ions

    Energy Technology Data Exchange (ETDEWEB)

    Labzowsky, L.N. [Institute of Physics, St. Petersburg State University, Uljanovskaya 1, Petrodvorets, 198904 St. Petersburg (Russian Federation) and Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Petersburg (Russian Federation)]. E-mail: leonti@landau.phys.spbu.ru; Shonin, A.V. [Institute of Physics, St. Petersburg State University, Uljanovskaya 1, Petrodvorets, 198904 St. Petersburg (Russian Federation)

    2004-12-06

    The quantum electrodynamical (QED) theory of the two-photon transitions in hydrogenlike ions is presented. The emission probability for 2s1/2->2{gamma}(E1)+1s1/2 transitions is calculated and compared to the results of the previous calculations. The emission probabilities 2p1/2->{gamma}(E1)+{gamma}(E2)+1s1/2 and 2p1/2->{gamma}(E1)+{gamma}(M1)+1s1/2 are also calculated for the nuclear charge Z values 1=

  17. Remarks on the BRST-cohomology for $c_M > 1$ matter coupled to ``Liouville gravity"

    CERN Document Server

    Bilal, Adel

    1992-01-01

    We describe the (chiral) BRST-cohomology of matter with central charge $10$) and ghost-numbers 0 or $-1$ (for $r<0$). The (chiral) ground ring is isomorphic to a subring of the $c_M =1$ theory which is $(xy)^n,\\ n=0,1,2,\\ldots$, and there are {\\it no} non-trivial currents acting on the ground ring. In case b) there is no non-trivial relative cohomology for non-zero ghost numbers and, for zero ghost number, the cohomology groups are isomorphic to a $(D-1)$-dimensional on-shell ``transverse" Fock space. The only exceptions are at level 1 for vanishing matter momentum and $p_L=Q_L(1+r)$ with $r=\\pm 1$, where one has one more ghost-number zero and a ghost-number $r$ cohomology state. All these results follow quite easily from the existing literature.

  18. BRST cohomology ring in $\\widehat{c}_{M}$ $<$ 1 NSR string theory

    CERN Document Server

    Panda, S; Panda, Sudhakar; Roy, Shibaji

    1995-01-01

    The full cohomology ring of the Lian-Zuckerman type operators (states) in {\\hat c_M}<1 Neveu-Schwarz-Ramond (NSR) string theory is argued to be generated by three elements x, y and w in analogy with the corresponding results in the bosonic case. The ground ring generators x and y are non-invertible and belong to the Ramond sector whereas the higher ghost number operators are generated by an invertible element w with ghost number one less than that of the ground ring generators and belongs to either Neveu-Schwarz (NS) or Ramond (R) sector depending on whether we consider (even, even) or (odd, odd) series coupled to 2d supergravity. We explicitly construct these operators (states) and illustrate our result with an example of pure Liouville supergravity.

  19. The Matrix protein M1 from influenza C virus induces tubular membrane invaginations in an in vitro cell membrane model

    Science.gov (United States)

    Saletti, David; Radzimanowski, Jens; Effantin, Gregory; Midtvedt, Daniel; Mangenot, Stéphanie; Weissenhorn, Winfried; Bassereau, Patricia; Bally, Marta

    2017-01-01

    Matrix proteins from enveloped viruses play an important role in budding and stabilizing virus particles. In order to assess the role of the matrix protein M1 from influenza C virus (M1-C) in plasma membrane deformation, we have combined structural and in vitro reconstitution experiments with model membranes. We present the crystal structure of the N-terminal domain of M1-C and show by Small Angle X-Ray Scattering analysis that full-length M1-C folds into an elongated structure that associates laterally into ring-like or filamentous polymers. Using negatively charged giant unilamellar vesicles (GUVs), we demonstrate that M1-C full-length binds to and induces inward budding of membrane tubules with diameters that resemble the diameter of viruses. Membrane tubule formation requires the C-terminal domain of M1-C, corroborating its essential role for M1-C polymerization. Our results indicate that M1-C assembly on membranes constitutes the driving force for budding and suggest that M1-C plays a key role in facilitating viral egress. PMID:28120862

  20. Sequence Characterization of matrix protein (M1 in influenza A viruses (H1, H3 and H5

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    2011-10-01

    Full Text Available This study brings the analysis of amino acid sequences of matrix protein (M1 from the influenza virus A (H1N1, H3N2 and H5N1 during 2007-2208. 741 sequences of M1 were compared, of them, H1N1 388; H3N2 251 and H5N1 102. Even though, the M1 is relatively conserved among the influenza A viruses, we found some variations in the M1 among the viruses, H1N1, H3N2 and H5N1. The nuclear localization signal at amino acid 101 to 105 is RKLKR for H1N1 and H3N2, but for H5N1 is KKLKR. All differences of amino acid in M1 of H1, H3 and H5 were listed. 80 sequences of M1 of H1N1 H3N2 and H5N1 were used for phylogenetic analysis. There is no reasontantment found in the M1 among these subtypes. Further study is needed to study the differences of the function of M1 among H1N1, H3N2 and H5N1. The M1 of H5N1 may contribute to the high pathogenesis to this virus.

  1. Seasonal milk contamination by aflatoxin m1, organophosphates and carbamates in Paraná – Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Crispim de Oliveira Ramos

    2016-08-01

    Full Text Available Aiming to evaluate the milk contamination in the dairy production systems (DPS for mycotoxins and chemical residues of organophosphates and carbamates it was made a study encompassing 96 DPS in three regions of Parana state. There were collected samples of milk, water and food and they were evaluated for chemical residues in all samples and aflatoxin only for food and milk. Mycotoxins in food (aflatoxin B1, B2, G1, G2, zearalenone and ochratoxin were detected by the method of thin layer chromatography – TLC and for the determination of aflatoxin M1 was used an immunoassay kit competitive ELISA Ridascreen®. The residues of organophosphates and carbamates were performed by colorimetric method qualitatively. There were evaluated the differences between regions, periods and the sources of mycotoxin contamination. Carbamates and organophosphates were screened for their presence in milk and the sources of food and water. Then it was estimated the contributions of each mycotoxin for milk contamination, as well as their respective contaminated food. Differences were found between periods (p < 0,05 for milk contamination with aflatoxin M1 – AFM1. For carbamates and organophosphates were found different contamination sources (p < 0,01. For the carbamates the source were pesticides used to parasitic herd control and for the organophosphates pesticides used in agriculture. For food sources contamination resulting in the AFM1 contamination it was detected that aflatoxin B1 – AFB1 was the main source. The aflatoxin G1 – AFG1 showed a strong correlation (p < 0,01 with AFB1 levels suggesting causal relationship is a function of fungal strains producing both at the same time. It was also found the prevalence of aflatoxin contamination in 70% of contaminated samples and its predominant presence in relation to other mycotoxins in all kinds of foods analyzed. By identifying the checkpoints of contamination can be proposed the inclusion of practical

  2. The frequency of occurrence of aflatoxin M1 in milk on the territory of Vojvodina

    Directory of Open Access Journals (Sweden)

    Polovinski-Horvatović Miroslava S.

    2009-01-01

    Full Text Available Aflatoxin is one of the most common mycotoxins which can be found in milk. It represents a natural metabolite of aflatoxin B1 that occurs as a result of animal metabolism and the body's attempt to detoxificate it. It is excreted in milk, feces and urine of animals that consumed contaminated feed with aflatoxin B1. The carry-over from feed to milk depends on many factors, ranging from 0.3 to 6.2%. Aflatoxin M1 is in the first group of carcinogens according to the IRAC classification from 2002, but it is considered to have only 10% of carcinogenicity from its precursor aflatoxin B1. Legislation in member countries of European Union for this mycotoxin in milk intended for people is 0.05 μg/l, while the rest of the countries that also have legislation for this mycotoxin allow the concentration that is ten times higher, and that is 0.5 μg/l. In this paper, we have tried to provide on insight into the quality of milk, food often consumed by children, from the standpoint of mycotoxicology, and to compare the obtained data with data available from literature, from countries in the region that have similar climatic and agricultural conditions. From a total of 65 samples of processed milk, aflatoxin M1 was found in 18 samples and none of the samples exceeded the level of 0.05 μg/l, which is allowed by the legislation of the European Union.

  3. In Vivo Measurements in Mice in the Bion-M 1 Mission

    Science.gov (United States)

    Andreev-Andrievskiy, Alexander; Custaud, Marc-Antoine; Popova, Anfisa; Borovik, Anatoliy; Dolgov, Oleg; Anokhin, Konstantin; Tsvirkun, Daria; Vinogradova, Olga

    The main aim of BION-M 1 mission was to reveal morphological, biochemical and molecular mechanisms of adaptation to prolonged exposure in microgravity. Besides that functional state and behavior were assessed in vivo using test battery, home cage observations and implantable telemetry in space-flown mice (SF), control mice from the ground replica of the flight experiment (GC) and in mice kept in vivarium (SFV and GCV). Blood pressure and heart rate were monitored continuously in a subgroup of mice using implantable telemetry throughout the flight as well as before and after it. After 30-days flight aboard BION-M 1 biosatellite SF mice have gained more weight than GC, SFV or GCV mice (11%). SF mice displayed pronounced motor impairment upon examination shortly after landing. 1 day after the flight mice were less active and more anxious in the open-field test, less coordinated in the Rotarod and aerial drop test and had less grip force compared to both control and pre-flight values. Exercise performance was greatly reduced after 30-days flight and recovered by day 7 post-flight. Before the flight mice were trained to perform a simple task using positively reinforced free operant conditioning approach. After the flight performance in the same task was preserved, however learning ability was impaired. Mice displayed drastic reduction of heart rate during launch and reentry acceleration periods. Heart rate (by 8-10%) and, to a lesser extent blood pressure (by 5%) were elevated during the 30-days flight. After return heart rate in SF mice remained elevated throughout the 7-days observation period with no apparent recovery. In summary, mice display pronounced disadaptation to 1g after 30-days exposure in microgravity with different physiological systems having different recovery dynamics. Of particular interest, hemodynamic reactions in mice closely resemble reactions in larger organisms, implying that factors that govern the cardiovascular system adaptation to

  4. The M1 muscarinic antagonist pirenzepine reduces myopia and eye enlargement in the tree shrew.

    Science.gov (United States)

    Cottriall, C L; McBrien, N A

    1996-06-01

    To determine the efficacy of the M1-selective muscarinic antagonist, pirenzepine, in preventing experimentally induced myopia in a mammalian model, the tree shrew. Tree shrews were monocularly deprived (MD) using translucent goggles or negative lenses for a period of 12 days. In two of the MD groups, tree shrews received daily subconjunctival administration of either pirenzepine (17.7 mumol; n = 9) or vehicle control (n = 6). Control groups (n = 6) were used to assess the effects of MD, injection regimen, and drug effects. In sham-injected and saline-injected MD tree shrews, 12 days of MD produced-13.2 D +/- 0.8 D and -14.1 D +/- 0.5 D of axial myopia, respectively. In pirenzepine-injected MD tree shrews, 12 days of MD induced an axial myopia of only -2.1 D +/- 1.4 D. The significant reduction in myopia in pirenzepine-injected MD tree shrews was caused by significantly less vitreous chamber elongation of the deprived eye (0.05 mm +/- 0.04 mm) relative to the contralateral control eye when compared to sham-injected and saline-injected MD tree shrews (0.24 mm +/- 0.02 mm and 0.29 mm +/- 0.01 mm). Mean equatorial enlargement and increased eye weight were prevented in pirenzepine-injected MD tree shrews (P Pirenzepine also was found to reduce myopia and ocular enlargement in lens defocus-induced myopia. Control experiments demonstrated that pirenzepine did not cause a significant reduction in amplitude of carbachol-induced accommodation. Findings demonstrate that chronic administration of the M1-selective muscarinic antagonist, pirenzepine, prevents experimentally induced myopia in this mammalian model by a nonaccommodative mechanism.

  5. Paracoccin Induces M1 Polarization of Macrophages via Interaction with TLR4

    Science.gov (United States)

    Freitas, Mateus S.; Oliveira, Aline F.; da Silva, Thiago A.; Fernandes, Fabrício F.; Gonçales, Relber A.; Almeida, Fausto; Roque-Barreira, Maria C.

    2016-01-01

    The fungal human pathogen Paracoccidioides brasiliensis contains paracoccin (PCN), a multi-domain protein that has lectin and N-acetyl-glucosaminidase activities, which account for its effects on the growth and morphogenesis of the fungus and on the activation of host macrophages through its interaction with TLR N-glycans. With the purpose of detailing the knowledge on the effects of PCN on macrophages, we used recombinant PCN expressed in Pichia pastoris (p-rPCN) to stimulate isolated murine peritoneal macrophages. The activation of these cells manifested through the release of high levels of inflammatory mediators, such as nitric oxide, TNF-α, IL-12p40, and IL-6. Furthermore, peritoneal macrophages stimulated with p-rPCN increased the relative expression of STAT1, SOCS3, and iNOS2 mRNA (M1 polarization markers). However, the expression of Arginase-1, Ym-1, and FIZZ1 (M2 polarization markers) remained at basal levels. Interestingly, the observed M1 macrophages’ polarization triggered by p-rPCN was abolished in cells obtained from knockout Toll-like receptor-4 mice. In this case, the p-rPCN-induced production of pro-inflammatory mediators was blocked too. These results demonstrate that the classical activation of macrophages induced by paracoccin depends on TLR4. Taken together, the results of our study indicate that paracoccin acts as a TLR agonist able to modulate immunity and exerts biological activities that favor its applicability as an immunotherapeutic agent to combat systemic fungal infections. PMID:27458431

  6. Composition of breccia matrices from the Manson M-1 drill core

    Science.gov (United States)

    Kracher, A.; Anderson, R. R.; Koeberl, C.

    1994-07-01

    Eleven drill cores were recently recovered from the Manson, Iowa, impact structure. Core M-1, which was drilled at the edge of the large central uplift, contains three major impact rock types: sedimentary clast breccia, melt matrix breccia, and fragmental breccia. Breccia matrices from different depths in the M-1 core were investigated by defocused beam electron probe microanalysis. To obtain average compositions, matrix areas free of lithic and mineral clasts were covered with an orthogonal grid of analyses points. Variations in composition have two main causes: differences in source lithology and postimpact processes. With increasing depth distinct changes in composition can be observed. All compositions are highly feldspathic and surprisingly low in SiO2 for putative source lithologies of mostly granitic composition. Within the lithological units containing melt matrix breccia increasing recrystallization can be observed with depth. Compositions in this interval are marginally corundum normative and not as high in normative feldspar as other matrices. The thoroughly recrystallized matrices from the lowest intervals of the melt matrix breccia are more feldpathic, higher in Na/K ratio, and not corundum normative. Unlike the chemical variation between rock types, we tentatively ascribe the chemical changes within the melt matrix breccia to reaction of matrix with clasts. In particular, quartz clasts in breccias with highly recrystallized matrices develop fringes of K-spar, cpx, and ilmenite. The formation of these minerals is presumably accompanied by complementary changes in matrix composition. Factor analysis on data sets of individual melt matrix analyses provides further clues to the influence of source lithology and post impact processes respectively in the chemical makeup of the breccia matrices. The most significant factors are a mafic component and a plagioclase component.

  7. Distant and new mutations in CTX-M-1 beta-lactamase affect cefotaxime hydrolysis.

    Science.gov (United States)

    Pérez-Llarena, Francisco José; Kerff, Frédéric; Abián, Olga; Mallo, Susana; Fernández, María Carmen; Galleni, Moreno; Sancho, Javier; Bou, Germán

    2011-09-01

    The CTX-M β-lactamases are an increasingly prevalent group of extended-spectrum β-lactamases (ESBL). Point mutations in CTX-M β-lactamases are considered critical for enhanced hydrolysis of cefotaxime. In order to clarify the structural determinants of the activity against cefotaxime in CTX-M β-lactamases, screening for random mutations was carried out to search for decreased activity against cefotaxime, with the CTX-M-1 gene as a model. Thirteen single mutants with a considerable reduction in cefotaxime MICs were selected for biochemical and stability studies. The 13 mutated genes of the CTX-M-1 β-lactamase were expressed, and the proteins were purified for kinetic studies against cephalothin and cefotaxime (as the main antibiotics). Some of the positions, such as Val103Asp, Asn104Asp, Asn106Lys, and Pro107Ser, are located in the (103)VNYN(106) loop, which had been described as important in cefotaxime hydrolysis, although this has not been experimentally confirmed. There are four mutations located close to catalytic residues-Thr71Ile, Met135Ile, Arg164His, and Asn244Asp-that may affect the positioning of these residues. We show here that some distant mutations, such as Ala219Val, are critical for cefotaxime hydrolysis and highlight the role of this loop at the top of the active site. Other distant substitutions, such as Val80Ala, Arg191, Ala247Ser, and Val260Leu, are in hydrophobic cores and may affect the dynamics and flexibility of the enzyme. We describe here, in conclusion, new residues involved in cefotaxime hydrolysis in CTX-M β-lactamases, five of which are in positions distant from the catalytic center.

  8. 乳品中黄曲霉毒素M1检测方法研究进展%Review on detection methods of aflatoxin M1 in dairy products

    Institute of Scientific and Technical Information of China (English)

    黄亚伟; 魏光; 王若兰; 罗莉

    2014-01-01

    Aflatoxin M1 is the metabolite of aflatoxin B1 after being intaken by animals. It mainly appears in animals’ milk and urine. Aflatoxin M1 is very toxic, ingestion of which by dairy will produce a great harm to the human body. This paper focused on the toxicity, hazards, and detection methods of aflatoxin M1 in dairy. The main characteristics and scope of the detection methods were analyzed and summarized, and the develop-ment of detection of aflatoxin M1 were also reasonably prospected.%黄曲霉毒素M1是动物摄入黄曲霉毒素B1后的代谢产物,主要分布在动物的乳汁、尿液中。黄曲霉毒素 M1毒性很大,经乳制品摄入会对人体产生巨大的危害。本文主要对乳品中黄曲霉毒素 M1毒性、危害、检测方法进行综述。对主要检测方法的特性及适用范围进行分析与概括,并且对未来黄曲霉毒素M1的检测方法的发展进行了合理展望。

  9. 叉头框蛋白 M1在乳腺癌的进展及治疗耐药中的作用%The role of FoxM1 in the development and treatment of breast cancer

    Institute of Scientific and Technical Information of China (English)

    李蕙颖(综述); 耿敬姝(审校)

    2016-01-01

    FoxM1 is a specific transcription factor related to proliferation .Previous studies have found that FoxM1 can enhance the proliferation ,metastasis and invasion of cancer cells ,and play a crucial role in canc-er.Recent studies indicate that the abnormal expression of FoxM 1 plays an important role in breast cancer ,and its overexpression is negatively correlated with the overall survival of patients .For the early diagnosis of breast canc-er,clinical prognosis and study on combination therapy provides a new direction .This article reviews the relation-ship between FoxM1 and breast cancer .%叉头框蛋白质M1(Forkhead box protein M1,FoxM1)是一种特异性的与增殖相关的转录因子。既往研究发现,FoxM1具有增强癌细胞增殖、转移和侵袭的功能,在肿瘤的发生发展中扮演着至关重要的角色。近年来研究表明,FoxM1的异常表达在乳腺癌的发生及发展中起着重要的作用,且其过表达与肿瘤患者的总生存期的关系呈负相关,为乳腺癌的早期诊断、临床预后及联合治疗提供了新的研究方向,本文就FoxM1与乳腺癌的关系做一综述。

  10. Reserves in western basins

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  11. Origin of Harmattan dust settled in Northern Ghana – Long transported or local dust?

    DEFF Research Database (Denmark)

    Lyngsie, Gry; Awadzi, Theodore W; Breuning-Madsen, Henrik

    2011-01-01

    compositions of the bulk dust samples. Traces of minerals in the clay fraction of the Harmattan period dust may have their origin in the Bodélé Depression or other saline environments. The Harmattan dust deposited in Ghana shows only little resemblance to dust from the Chad basin and with Harmattan dust...... deposited in Niger. This study therefore suggests that the dust deposited during the Harmattan period in northern Ghana is not under significant influence of sediments from the Bodélé Depression. Similarity in the mineral and elemental composition of the dust from both the Harmattan and Monsoon periods...

  12. Combined physico-chemical treatment of secondary settled municipal wastewater in a multifunctional reactor.

    Science.gov (United States)

    Santoro, O; Pastore, T; Santoro, D; Crapulli, F; Raisee, M; Moghaddami, M

    2013-01-01

    In this paper, the physico-chemical treatment of municipal wastewater for the simultaneous removal of pollutant indicators (chemical oxygen demand (COD) and total coliforms) and organic contaminants (total phenols) was investigated and assessed. A secondary settled effluent was subjected to coagulation, disinfection and absorption in a multifunctional reactor by dosing, simultaneously, aluminum polychloride (dose range: 0-150 μL/L), natural zeolites (dose range: 0-150 mg/L), sodium hypochlorite (dose range: 0-7.5 mg/L) and powder activated carbon (dose range: 0-30 mg/L). The treatment process was optimized using computational fluid dynamics (CFD) and response surface methodology. Specifically, a Latin square technique was employed to generate 16 combinations of treating agent types and concentrations which were pilot tested on an 8 m(3)/h multifunctional reactor fed by a secondary effluent with COD and total coliform concentrations ranging from ≈20 to 120 mg/L and from 10(5) to 10(6) CFU/100 mL, respectively. Results were promising, indicating that removal yields up to 71% in COD and 5.4 log in total coliforms were obtained using an optimal combination of aluminum polychloride (dose range ≈ 84-106 μL/L), powder activated carbon ≈ 5 mg/L, natural zeolite (dose range ≈ 34-70 mg/L) and sodium hypochlorite (dose range ≈ 3.4-5.6 mg/L), with all treating agents playing a statistically significant role in determining the overall treatment performance. Remarkably, the combined process was also able to remove ≈ 50% of total phenols, a micropollutant known to be recalcitrant to conventional wastewater treatments.

  13. Experiments of ECCS strainer blockage and debris settling in suppression pools

    Energy Technology Data Exchange (ETDEWEB)

    Hecker, G.E.; Johnson, A.B.; Murthy, P.; Padmanabhan

    1996-03-01

    If a rupture occurs in a nuclear power station pipe that leads to or from the reactor pressure vessel, the resultant Loss of Coolant Accident (LOCA) would initiate a chain of events involving complex flow phenomena. In a Boiling Water Reactor (BWR), the steam or liquid pipe break pressurizes the dry well, forcing the inert containment gases and steam through downcomers into the suppression pool, thoroughly mixing any particulates and pipe insulation debris carried with the gas flow to the pool. As the steam flow decreases, its unsteady condensation at the end of the downcomers (Condensation Oscillation and Chugging) produces continued water motion in the suppression pool and downcomers. During the blowdown event, high pressure and then low pressure pumps automatically start injecting water from the suppression pool into the reactor to keep its temperature under control. Proper functioning of this Emergency Core Cooling System (ECCS) is critical for the first 30 minutes or so, before operators have time to consider and align alternative sources of cooling water. A major concern for proper operation of the ECCS is the effect of fragmented insulation and plant particulates on the head loss at pump suction strainers. Sufficient loss could exceed the NPSH margin, causing cavitation with a resultant loss of pump capacity and longevity. The bead loss increases with the mass of debris accumulated on the pump strainers, which in turn is dependent on the debris concentration versus time in the suppression pool. This paper describes two sets of experiments that quantified the strainer head loss. One set of experiments considered the mixing and settling of fibrous insulation debris and fine iron oxide particles in the suppression pool during and after chugging. These tests used a reduced scale facility which duplicated the kinetic energy per unit water volume to define the concentration of the actual materials in the pool versus time.

  14. [Characterisation of excess sludge reduction in an anoxic + oxic-settling-anaerobic activated sludge process].

    Science.gov (United States)

    Gao, Xu; Lu, Yan-Hua; Guo, Jin-Song

    2009-05-15

    An energy balance analysis method with auto calorimeter being adopted was introduced to determine calorific values of sludge samples in influent and effluent of uncoupling tank in an anoxic (A) + oxic-settling-anaerobic (OSA) process and a reference system. The affiliation of sludge amount change and its energy content were studied, as well as potential of excess sludge reduction was evaluated through modifying performance of uncoupling tank. The characteristi s and causes of sludge reduction in OSA system were deduced according to energy and matter balance analysis. Results show that when the hydraulic retention time (HRT) of uncoupling tank are 5.56 h, 7.14 h and 9 h, the excess sludge reduction of whole A + OS Asystem are 1.236 g/d, 0.771 g/d and 0.599 g/d respectively. Energy content of sludge flows into and out of the uncoupling tank changes, the specific calorific value of sludge in effluent is inclined to be higher than that in influent with the HRT of the tank increasing: there isn't any significant difference of sludge calorific values between influent and effluent at 5.56 h, while the differences are in 99-113 J/g at 7.14 h, and 191-329 J/g at 9 h. Sludge in uncoupling tank would decay and longer HRT will result in more attenuation. It could be concluded that excess sludge reduction of A + OSA system is caused by both of sludge decay in uncoupling tank and sludge proliferation in AO reaction zone.

  15. On the Instability of Spheres Settling through a Vertical Pipe Filled with HPG

    Directory of Open Access Journals (Sweden)

    Patrick Weidman

    2012-01-01

    Full Text Available An extensive set of experiments were performed to determine the stability boundary for the longitudinal oscillation of steel spheres settling through Hydroxy Propyl Guar (HPG contained in long vertical tubes, a phenomenon first reported by Mollinger, et al. (1999. Results are reported in d/D-pH parameter space, where d is the sphere diameter and D is the internal diameter of a tube. Longitudinal oscillations, which owe their existence to the self-healing nature of the gel, occur over the region 0.48 < d/D < 0.86 and 8.31 < pH < 8.82. We discover that the upper pH limit of this stability domain is linked to the HPG gel point. During the course of experimentation, additional instabilities in the form of high-frequency transverse oscillations or helical motions were discovered and documented. The pure transverse oscillations found in the domain 8.035 < pH < 8.31 and 0.9 < d/D < 0.6 result from the elastic nature of the guar in this region. For 6.25 < pH < 8.035 transverse oscillations or stable descents are interspersed between bands of tight helical motion at large d/D and wide helical motion at low d/D. At the lowest value pH = 6.25 the guar is a Newtonian fluid, yet the spiral motion persists in small bands of d/D. We have verified, in the literature and through additional experiments using distilled water as the Newtonian liquid that the spiral motion of spheres falling inside vertical tubes does indeed exist.

  16. Bench-scale enhanced sludge washing and gravity settling of Hanford Tank C-106 Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, K.P; Myers, R.L; Rappe, K.G.

    1997-01-01

    This report summarizes the results of a bench-scale sludge pretreatment demonstration of the Hanford baseline flowsheet using liter-quantities of sludge from Hanford Site single-shell tank 241-C-106 (tank C-106). The leached and washed sludge from these tests provided Envelope D material for the contractors supporting Tank Waste Remediation System (TWRS) Privatization. Pretreatment of the sludge included enhanced sludge washing and gravity settling tests and providing scale-up data for both these unit operations. Initial and final solids as well as decanted supernatants from each step of the process were analyzed chemically and radiochemically. The results of this work were compared to those of Lumetta et al. (1996a) who performed a similar experiment with 15 grams of C-106, sludge. A summary of the results are shown in Table S.1. Of the major nonradioactive components, those that were significantly removed with enhanced sludge washing included aluminum (31%), chromium (49%), sodium (57%), and phosphorus (35%). Of the radioactive components, a significant amount of {sup 137}Cs (49%) were removed during the enhanced sludge wash. Only a very small fraction of the remaining radionuclides were removed, including {sup 90}Sr (0.4%) and TRU elements (1.5%). These results are consistent with those of the screening test. All of the supernatants (both individually and as a blend) removed from these washing steps, once vitrified as LLW glasses (at 20 wt% Na{sub 2}O), would be less than NRC Class C in TRU elements and less than NRC Class B in {sup 90}Sr.

  17. The preparation of milkpowder contaminated with aflatoxin M1. Investigations of the homogeneity and stability of the product

    NARCIS (Netherlands)

    Egmond; H.P.van; Sizoo; E.A.

    1984-01-01

    Ten behoeve van BCR werd een hoeveelheid melkpoeder bereid, langs natuurlijke weg besmet met aflatoxine M1 op een niveau van ca. 1 mug/kg. Onderzoek naar de homogeniteit van het materiaal wees uit dat aflatoxine M1 homogeen verdeeld was over de geproduceerde melkpoeder. Voorts bleek dat beware

  18. Nuclear export of the influenza virus ribonucleoprotein complex: Interaction of Hsc70 with viral proteins M1 and NS2.

    Science.gov (United States)

    Watanabe, Ken; Shimizu, Teppei; Noda, Saiko; Tsukahara, Fujiko; Maru, Yoshiro; Kobayashi, Nobuyuki

    2014-01-01

    The influenza virus replicates in the host cell nucleus, and the progeny viral ribonucleoprotein complex (vRNP) is exported to the cytoplasm prior to maturation. NS2 has a nuclear export signal that mediates the nuclear export of vRNP by the vRNP-M1-NS2 complex. We previously reported that the heat shock cognate 70 (Hsc70) protein binds to M1 protein and mediates vRNP export. However, the interactions among M1, NS2, and Hsc70 are poorly understood. In the present study, we demonstrate that Hsc70 interacts with M1 more strongly than with NS2 and competes with NS2 for M1 binding, suggesting an important role of Hsc70 in the nuclear export of vRNP.

  19. F-box protein FBXL2 inhibits gastric cancer proliferation by ubiquitin-mediated degradation of forkhead box M1.

    Science.gov (United States)

    Li, Liang-qing; Pan, Dun; Chen, Hui; Zhang, Lin; Xie, Wen-jun

    2016-02-01

    F-box/LRR-repeat protein 2 (FBXL2), a component of Skp-Cullin-F box (SCF) ubiquitin E3 ligase, has been shown to inhibit tumorigenesis by targeting and ubiquitinating several oncoproteins. However, its role in gastric cancer remains poorly understood. Here, by tandem mass spectrometry, we show that FBXL2 interacts with forkhead box M1 (FoxM1) transcription factor. As a result, FBXL2 promotes ubiquitination and degradation of FoxM1 in gastric cancer cells. Furthermore, overexpression of FBXL2 inhibits, while its deficiency promotes cell proliferation and invasion. Expression levels of cell-cycle regulators (Cdc25B and p27), which are down-stream target effectors of FoxM1, are also regulated by FBXL2. Therefore, our results uncover a previous unknown network involving FBXL2 and FoxM1 in the regulation of gastric cancer growth.

  20. Action of peracetic acid on Escherichia coli and Staphylococcus aureus in suspension or settled on stainless steel surfaces

    Directory of Open Access Journals (Sweden)

    Kunigk Leo

    2001-01-01

    Full Text Available The efficiency of a commercial peracetic acid sanitizer on destruction of Staphylococcus aureus and Escherichia coli was evaluated using two distinct methods. The first method is the AOAC suspension test and the second is a method proposed by one of the authors in which the microbial cells are settled on a stainless steel surface and then treated with the sanitizer. The results showed that when in suspension S. aureus was more resistant to the sanitizer than E. coli. When S. aureus was settled on the stainless steel surface, the contact time between the sanitizer and the microorganisms to attain a 6.5 log reduction in the number of viable cells was three times greater than when the cells were in suspension.