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A Semianalytical Model Using MODIS Data to Estimate Cell Density of Red Tide Algae (Aureococcus anophagefferens)
A multiband and a single-band semianalytical model were developed to predict algae cell density distribution. The models were based on cell density (N) dependent parameterizations of the spectral backscattering coefficients, b ( ), obtained from in situ measurements. There was a strong relationship between b ( ) and N, with a minimum regression coefficient of 0.97 at 488 nm and a maximum value of 0.98 at other bands. The cell density calculated by the multiband inversion model was similar to the field measurements of the coastal waters (the average relative error was only 8.9%), but it could not accurately discern the red tide from mixed pixels, and this led to overestimation of the area affected by the red tide. While the single-band inversion model is less precise than the former model in the high chlorophyll water, it could eliminate the impact of the suspended sediments and make more accurate estimates of the red tide area. We concluded that the two models both have advantages and disadvantages; these methods lay the foundation for developing a remote sensing forecasting system for red tides
Desensitization is a property of the cholinergic binding region of the nicotinic acetylcholine receptor, not of the receptor-integral ion channel
The reversible acctylchollne esternse inhibitor (-}.physostiilmine (¢serine) is th© prolotypc of a new class of nie~tinlc ucetylcholinc receptor (nAChR) activating liga,ds: it induces cation fluxes into nAChR.rich membrane vesicl~s from 7~r#eda marmoeata cle~:tric tissue even under condl. lions of antalionist blocked :tcctylcholin~ binding sil~s (Okonjo, Kuhlm~mn. Maelicke. Neuron, in press). This su~tlest's that escrine exerts it~ than. nel.activating proi'~rty via binding sites at the nAChR separate from those of tile natural transmitter. We now report thllt eserine e'-m activate the channel wen when the receptor has t~en preincub~ttcd (des©nsitiz©d) with elevated concentrations of acetylcholi~e, Titus the confornudional state Of the receptor corresponding to de~nsitixation is confined to the transmitter bindinB rclli0n, leaving the ch=tr'4nel fully activatable ,-albeit only from other than the tr~msmitter bindin~ site(s)
Discussion Paper Series The Impact of Immigration on the UK Labour Market The Impact of Immigration on the UK Labour Market
Abstract This paper provides an empirical investigation of the way immigration affects labour market outcomes of native born workers in the UK, set beside a theoretical discussion of the underlying economic mechanisms. We discuss the problems that may arise in empirical estimations, and suggest ways to address these problems. Our empirical analysis is based on data from the British Labour Force Survey. We show that the overall skill distribution of Britain's immigrant workforce is remarkably similar to that of the native born workforce. We investigate the impact of immigration on employment, participation, unemployment and wages of the resident population. We find no evidence that immigration has overall effects on any of these outcomes at the aggregate level. There is some evidence that effects are different for different educational groups. Abstract This paper provides an empirical investigation of the way immigration affects labour market outcomes of native born workers in the UK, set beside a theoretical discussion of the underlying economic mechanisms. We discuss the problems that may arise in empirical estimations, and suggest ways to address these problems. Our empirical analysis is based on data from the British Labour Force Survey. We show that the overall skill distribution of Britain's immigrant workforce is remarkably similar to that of the native born workforce. We investigate the impact of immigration on employment, participation, unemployment and wages of the resident population. We find no evidence that immigration has overall effects on any of these outcomes at the aggregate level. There is some evidence that effects are different for different educational groups
Haptic Effects Modulate Kinetics of Gait but not Experience of Realism in a Virtual Reality Walking Simulator
Abstract-Presence in virtual environments is achieved when the user is immersed and experiences a sense of realism. Multi-modal feedback is used to create this sense of realism. This study tested the contributions of visual stimuli and haptic effects to the users' sense of realism on a walking simulator. Haptic effects were modeled as an icy or a muddy road surface. To determine if the haptic effects modified gait we also measured the temporal spatial and kinetic characteristics of walking. Eleven healthy adults walked on a simulator to cross a virtual street. Twenty two walking trials were randomly presented in which either Visual, haptic (floor effects), or combined visual and haptic effects were presented. Realism, feeling and seeing were rated after each trial using a visual analogue scale (VAS). Kinetic data were extracted from the mobility simulator force transducer for initial contact and initial swing. Kinematic data were collected using reflective markers and six-camera system. Reports of realism were not enhanced with the addition of floor effects. Kinetics of gait were modulated by haptic effects with a shorter step length and decreased force in the z (downward) direction during initial contact for ice (haptics alone) and increased forces in the x (forward) and z (upward) direction during initial swing for mud. A shortened step length and decreased velocity relative to over-ground walking may have masked the perception of the floor effects, even though subjects changed their gait kinetics
Integrity in Business: An Evaluation of Integrity across German and American Culture
Abstract Integrity is necessary in all of business. Without trust, basic business functions could not be performed, especially in struggling or developing businesses. This paper considers the relative importance of integrity across cultural lines through interviews with American and German business leaders. The content of the interviews and the issues of ethics and integrity across cultural lines is discussed
Ab Initio Identification of Novel Regulatory Elements in the Genome of Trypanosoma brucei by Bayesian Inference on Sequence Segmentation
Abstract Background: The rapid increase in the availability of genome information has created considerable demand for both comparative and ab initio predictive bioinformatic analyses. The biology laid bare in the genomes of many organisms is often novel, presenting new challenges for bioinformatic interrogation. A paradigm for this is the collected genomes of the kinetoplastid parasites, a group which includes Trypanosoma brucei the causative agent of human African trypanosomiasis. These genomes, though outwardly simple in organisation and gene content, have historically challenged many theories for gene expression regulation in eukaryotes
Development of Test Equipment for Measuring Compression Characteristics of Sheet Gaskets at Elevated Temperature
ABSTRACT Evaluation of the sealing performance of pipe flange connection is significantly important for the safety of pipe line structures. The compression characteristics of sheet gaskets primarily affect the mechanical behavior of flanged connections. It is known that the stiffness of sheet gaskets decreases with an increase in temperature. Therefore, the compression test must be conducted at various levels of elevated temperatures. From the experimental point of view, however, a great difficulty is involved in measuring the compression characteristics of gaskets at elevated temperature. For this reason, a definite testing procedure has not yet been established. In this paper, a prototype of compression test equipment has been developed for measuring the stress-strain curves of sheet gaskets at elevated temperature. The test equipment is compact and the experiments can be conducted with a fairly easy operation. It can control the gasket stress from zero to 30MPa while keeping the temperature of test specimen at different levels from room temperature to 300˚C and higher. Aramid sheet gaskets are selected as test specimens. Experimental results show that the gasket stiffness drops with an increase in temperature. The shapes of the compression curves at different temperatures are similar, and those curves move in the direction of lower stiffness as the temperature is increased. It is concluded that the test equipment proposed here has a high promise to measure the stress-strain curves of sheet gaskets and estimate the sealing performance of pipe flange connections at elevated temperature
Phase diagrams of mixtures of ethyl palmitate with fatty acid ethyl esters
Keywords: Cloud point Fatty acid ethyl ester (FAEE) Ethyl palmitate Solid-liquid equilibrium Predictive UNIQUAC a b s t r a c t The cloud point is an important property of biodiesel, controlling its low temperature behaviour, especially the fluidity of the fuel. Although biodiesel is an interesting renewable energy source, data for the melting/cloud point of biodiesel or simple binary or ternary mixtures of fatty acid ethyl esters (FAEE) are still scarce in the literature, particularly for those involving ethyl esters. The phase diagrams of six binary mixtures of ethyl palmitate with saturated and unsaturated fatty acid ethyl esters were determined by Differential Scanning Calorimetry (DSC). The determined systems were successfully described employing the UNIQUAC model. The experimental data indicates that the cloud point is controlled by the fatty acid ethyl ester in the mixture with higher melting temperature