Biogenic structures and cable bacteria interactions: redox domain residence times and the generation of complex pH distributions

2021 ◽  
Author(s):  
H Yin ◽  
RC Aller ◽  
Q Zhu ◽  
JY Aller
Keyword(s):  
Residence Times ◽  
Biogenic Structures

Dosimetry with 188Re-labelled monoclonal anti-CD66 antibodies

2006 ◽  
Vol 45 (03) ◽  
pp. 134-138 ◽  
Author(s):  
T. Kull ◽  
N. M. Blumstein ◽  
D. Bunjes ◽  
B. Neumaier ◽  
A. K. Buck ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Bone Marrow ◽  
Gamma Camera ◽  
Absorbed Dose ◽  
Correlation Coefficients ◽  
Residence Times ◽  
Reliable Prediction ◽  
Red Bone Marrow ◽  
Antibody Preparation ◽  
Simplified Method

SummaryAim: For the therapeutic application of radiopharmaceuticals the activity is determined on an individual basis. Here we investigated the accuracy for a simplified assessment of the residence times for a 188Re-labelled anti-CD66 monoclonal antibody. Patients, methods: For 49 patients with high risk leukaemia (24 men, 25 women, age: 44 ± 12 years) the residence times were determined for the injected 188Re-labelled anti-CD66 antibodies (1.3 ± 0.4 GBq, 5–7 GBq/mg protein, >95% 188Re bound to the antibody) based on 5 measurements (1.5, 3, 20, 26, and 44 h p.i.) using planar conjugate view gamma camera images (complete method). In a simplified method the residence times were calculated based on a single measurement 3 h p.i. Results: The residence times for kidneys, liver, red bone marrow, spleen and remainder of body for the complete method were 0.4 ± 0.2 h, 1.9 ± 0.8 h, 7.8 ± 2.1 h, 0.6 ± 0.3 h and 8.6 ± 2.1 h, respectively. For all organs a linear correlation exists between the residence times of the complete method and the simplified method with the slopes (correlation coefficients R > 0.89) of 0.89, 0.99, 1.23, 1.13 and 1.09 for kidneys, liver, red bone marrow, spleen and remainder of body, respectively. Conclusion: The proposed approach allows reliable prediction of biokinetics of 188Re-labelled anti-CD66 monoclonal antibody biodistribution with a single study. Efficient pretherapeutic estimation of organ absorbed dose may be possible, provided that a more stable anti-CD66 antibody preparation is available.

Autecology of scum producing bacteria

1998 ◽  
Vol 37 (4-5) ◽  
pp. 527-530 ◽  
Author(s):  
Hilde Lemmer ◽  
George Lind ◽  
Margit Schade ◽  
Birgit Ziegelmayer
Keyword(s):  
Wastewater Treatment ◽  
Cell Surface ◽  
Wastewater Treatment Plants ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Residence Times ◽  
Loading Conditions ◽  
Emulsifying Activity ◽  
Substrate Preferences

Non-filamentous hydrophobic scum bacteria were isolated from scumming wastewater treatment plants (WWTP) by means of adhesion to hydrocarbons. They were characterized with respect to taxonomy, substrate preferences, cell surface hydrophobicity, and emulsification capability. Their role during flotation events is discussed. Rhodococci are selected by hydrolysable substrates and contribute to flotation both by cell surface hydrophobicity and emulsifying activity at long mean cell residence times (MCRT). Saprophytic Acinetobacter strains are able to promote flotation by hydrophobicity and producing emulsifying agents under conditions when hydrophobic substrates are predominant. Hydrogenophaga and Acidovorax species as well as members of the Cytophaga/Flavobacterium group are prone to proliferate under low loading conditions and contribute to flotation mainly by emulsification.

Smoothing of stationary random signal in continuous flow mixer with gamma-distribution of residence times

1985 ◽  
Vol 50 (11) ◽  
pp. 2545-2557
Author(s):  
Pavel Hasal ◽  
Vladimír Kudrna ◽  
Jitka Vyhlídková
Keyword(s):  
Theoretical Analysis ◽  
Gamma Distribution ◽  
Continuous Flow ◽  
Random Signal ◽  
Linear Filter ◽  
Residence Times ◽  
Statistical Parameters ◽  
Basic Parameters

The paper is focused on a theoretical analysis of the function of continuous flow mixer with the so-called gamma-distribution of fluid residence times, used as a linear filter smoothing undesirable fluctuations of input properties. A relation is derived expressing the degree of smoothing of the signal passing through the system, as a function of statistical parameters of this signal and of gamma-distribution of fluid-residence times in the mixer. The analysis of this relation leads to conclusions concerning the prediction of the operation of smoothing mixers or the design of their basic parameters.

scholarly journals Jaws of Platynereis dumerilii: Miniature Biogenic Structures with Hardness Properties Similar to Those of Crystalline Metals

JOM ◽  
2021 ◽  
Author(s):  
Luis Zelaya-Lainez ◽  
Giuseppe Balduzzi ◽  
Olaf Lahayne ◽  
Kyojiro N. Ikeda ◽  
Florian Raible ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Indentation Depth ◽  
Organic Matrix ◽  
Structure Property ◽  
Structural Protein ◽  
Inductively Coupled ◽  
Property Relations ◽  
Biogenic Structures ◽  
Platynereis Dumerilii ◽  
Bristle Worms

AbstractNanoindentation, laser ablation inductively coupled plasma mass spectroscopy and weighing ion-spiked organic matrix standards revealed structure-property relations in the microscopic jaw structures of a cosmopolitan bristle worm, Platynereis dumerilii. Hardness and elasticity values in the jaws’ tip region, exceeding those in the center region, can be traced back to more metal and halogen ions built into the structural protein matrix. Still, structure size appears as an even more relevant factor governing the hardness values measured on bristle worm jaws across the genera Platynereis, Glycera and Nereis. The square of the hardness scales with the inverse of the indentation depth, indicating a Nix-Gao size effect as known for crystalline metals. The limit hardness for the indentation depth going to infinity, amounting to 0.53 GPa, appears to be an invariant material property of the ion-spiked structural proteins likely used by all types of bristle worms. Such a metal-like biogenic material is a major source of bio-inspiration.

On the time scales and structure of Lagrangian intermittency in homogeneous isotropic turbulence

2019 ◽  
Vol 867 ◽  
pp. 438-481 ◽  
Author(s):  
R. Watteaux ◽  
G. Sardina ◽  
L. Brandt ◽  
D. Iudicone
Keyword(s):  
Time Scales ◽  
Isotropic Turbulence ◽  
Flow Characteristics ◽  
Residence Times ◽  
Particle Trajectories ◽  
Local Flow ◽  
Available Energy ◽  
Homogeneous And Isotropic Turbulence ◽  
History Of ◽  
Optimum Manner

We present a study of Lagrangian intermittency and its characteristic time scales. Using the concepts of flying and diving residence times above and below a given threshold in the magnitude of turbulence quantities, we infer the time spectra of the Lagrangian temporal fluctuations of dissipation, acceleration and enstrophy by means of a direct numerical simulation in homogeneous and isotropic turbulence. We then relate these time scales, first, to the presence of extreme events in turbulence and, second, to the local flow characteristics. Analyses confirm the existence in turbulent quantities of holes mirroring bursts, both of which are at the core of what constitutes Lagrangian intermittency. It is shown that holes are associated with quiescent laminar regions of the flow. Moreover, Lagrangian holes occur over few Kolmogorov time scales while Lagrangian bursts happen over longer periods scaling with the global decorrelation time scale, hence showing that loss of the history of the turbulence quantities along particle trajectories in turbulence is not continuous. Such a characteristic partially explains why current Lagrangian stochastic models fail at reproducing our results. More generally, the Lagrangian dataset of residence times shown here represents another manner for qualifying the accuracy of models. We also deliver a theoretical approximation of mean residence times, which highlights the importance of the correlation between turbulence quantities and their time derivatives in setting temporal statistics. Finally, whether in a hole or a burst, the straining structure along particle trajectories always evolves self-similarly (in a statistical sense) from shearless two-dimensional to shear bi-axial configurations. We speculate that this latter configuration represents the optimum manner to dissipate locally the available energy.

059 Daridorexant: A dual, equipotent, and insurmountable antagonist of both orexin-1 and orexin-2 receptors

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A25-A25
Author(s):  
Celia Mueller Grandjean ◽  
Manon Kiry ◽  
Catherine Vaillant ◽  
Oliver Nayler ◽  
John Gatfield
Keyword(s):  
Calcium Release ◽  
Brain Activity ◽  
Specific Treatment ◽  
Receptor Occupancy ◽  
Kinetic Properties ◽  
Receptor Subtypes ◽  
Residence Times ◽  
Binding Assays ◽  
Receptor System ◽  
Highly Effective

Abstract Introduction The orexin neuropeptide–receptor system is a central sleep and wake regulator in the brain. The two orexin receptor subtypes, OX1R and OX2R, are expressed either alone or together in all major wake-promoting brain areas. OX1R and OX2R activation by orexins causes elevation of intracellular calcium, which enhances synaptic transmission in secondary, monoaminergic wake- and arousal-promoting neurotransmitter circuits. Orexin receptor antagonists represent a novel and specific treatment of insomnia, which is different from classical therapy that more broadly inhibits brain activity via GABAA activation. Here we describe the molecular pharmacology of daridorexant, an orexin receptor antagonist which has proven highly effective in improving sleep and daytime functioning in insomnia patients. Methods Orexin-A(OxA)-induced calcium release assays in OX1R- and OX2R-expressing recombinant cell lines were applied to measure the antagonistic potency and kinetic properties of daridorexant in functional assays. Whole-cell competitive binding assays, using an orthosteric tracer were employed to determine the Ki of daridorexant. Comparisons were made with suvorexant and lemborexant. Results In OxA-induced calcium release assays with 2-h pre-incubation time, daridorexant displayed apparent Kb values of 0.5 nM (OX1R) and 0.8 nM (OX2R) with insurmountable antagonism on both receptors, demonstrating equipotent and highly effective functional inhibition of both receptor subtypes. On-target residence times of daridorexant (37oC) expressed as receptor occupancy half-lives (ROt1/2) were 4 min (OX1R) and 8 min (OX2R). In binding assays, daridorexant behaved as highly potent orthosteric antagonist. Also suvorexant behaved as dual insurmountable antagonist at OX1R/OX2R (appKb=0.7nM/1.0nM; ROt1/2=9 min/6 min) and as potent orthosteric antagonist in binding assays. Interestingly, lemborexant displayed a different interaction profile at OX1R/OX2R (appKb=13nM/0.4nM, ROt1/2<2min/<2min), i.e. it behaved as preferential OX2R antagonist with a very short on-target residence time and little insurmountability. Conclusion Daridorexant displays the desired target interaction profile of a dual, equipotent, and insurmountable antagonist of both OX1R and OX2R, which ensures equally efficient inhibition of both arousal-/wake-promoting receptor subtypes. Daridorexant′s on-target residence times are long enough to cause insurmountable inhibition, but short enough to avoid pharmacodynamic effects after drug elimination. Support (if any) Funded by Idorsia Pharmaceuticals Ltd.

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