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An algebraic theory for design of controllers for linear multivariable systems : Part II: Feedback realizations and feedback design

The study of general linear multivariable systems, with possibly different controlled and measured outputs, is continued in this part of the paper. The structure matrices, defined in Part I, are used to solve the feedback realization problem. Feedback realizable transfer functions are then used to solve problems of "regulator type." It is shown that the solutions to problems like disturbance deeou

A Regulator for Time-Varying Stochastic Systems

Some possible regulators are considered for control of stochastic systems, described by a time-varying difference equation. A new suboptimal dual algorithm is proposed, and its relation to other regulators is examined. It is discussed for what kind of systems the new algorithm will be advantageous, and when simpler schemes will suffice. This discussion is illustrated by simulations, where differen

Insights on Spectral Measures for HRV Based on a Novel Approach for Data Acquisition

In this paper, we present new insights on classical spectral measures for heart rate variability (HRV), based on a novel method for HRV acquisition. A dynamic breathing task, where the test participants are asked to breathe following a metronome with slowly increasing frequency, allows for the acquisition of respiratory-related HRV-data covering the frequency range in which adults breathe in diffe

Performance Limits in Adaptive Control

Minimum variance control of difference equation systems with time-varying stochastic parameters are studied. The optimal control law is derived under the assumption that all previous but not the current parameter values are known. This is used to give performance limits for dual control. In particular, it is shown that too much parameter uncertainty may cause the system to be unstable in the mean-

Implementation of concurrent Pascal on LSI—11

This paper considers the moving of the implementation of Concurrent Pascal for the PDP‐11/45 computer to the LSI‐11 computer. The resulting implementation for the LSI‐11 computer is also discussed and described

New Insights on the Role of Urea on the Dissolution and Thermally-Induced Gelation of Cellulose in Aqueous Alkali

The gelation of cellulose in alkali solutions is quite relevant, but still a poorly understood process. Moreover, the role of certain additives, such as urea, is not consensual among the community. Therefore, in this work, an unusual set of characterization methods for cellulose solutions, such as cryo-transmission electronic microscopy (cryo-TEM), polarization transfer solid-state nuclear magneti

Effective Interactions and Colloidal Stability of Bovine γ-Globulin in Solution

Interactions and phase behavior of γ-globulins are of fundamental interest in biophysical and pharmaceutical research, as these are among the most abundant proteins in blood plasma. In this work, we report the characterization of the oligomeric state of bovine γ-globulin, the effective protein–protein interactions, and the colloidal stability in aqueous solution as a function of protein concentrat

Strong Isotope Effects on Effective Interactions and Phase Behavior in Protein Solutions in the Presence of Multivalent Ions

In this article, we have studied the influence of the isotopic composition of the solvent (H2O or D2O) on the effective interactions and the phase behavior of the globular protein bovine serum albumin in solution with two trivalent salts (LaCl3 and YCl3). Protein solutions with both salts exhibit a reentrant condensation phase behavior. The condensed regime (regime II) in between two salt concentr

Cation-Induced Hydration Effects Cause Lower Critical Solution Temperature Behavior in Protein Solutions

The phase behavior of protein solutions is important for numerous phenomena in biology and soft matter. We report a lower critical solution temperature (LCST) phase behavior of aqueous solutions of a globular protein induced by multivalent metal ions around physiological temperatures. The LCST behavior manifests itself via a liquid-liquid phase separation of the protein-salt solution upon heating.

Analytical correlation functions for motion through diffusivity landscapes

Diffusion of a particle through an energy and diffusivity landscape is a very general phenomenon in numerous systems of soft and condensed matter. On the one hand, theoretical frameworks such as Langevin and Fokker-Planck equations present valuable accounts to understand these motions in great detail, and numerous studies have exploited these approaches. On the other hand, analytical solutions for

On the question of two-step nucleation in protein crystallization

We report a real-time study on protein crystallization in the presence of multivalent salts using small angle X-ray scattering (SAXS) and optical microscopy, focusing particularly on the nucleation mechanism as well as on the role of the metastable intermediate phase (MIP). Using bovine beta-lactoglobulin as a model system in the presence of the divalent salt CdCl2, we have monitored the early sta

Hierarchical molecular dynamics of bovine serum albumin in concentrated aqueous solution below and above thermal denaturation

The dynamics of proteins in solution is a complex and hierarchical process, affected by the aqueous environment as well as temperature. We present a comprehensive study on nanosecond time and nanometer length scales below, at, and above the denaturation temperature Td. Our experimental data evidence dynamical processes in protein solutions on three distinct time scales. We suggest a consistent phy

Salt-Induced Universal Slowing Down of the Short-Time Self-Diffusion of a Globular Protein in Aqueous Solution

The short-time self-diffusion D of the globular model protein bovine serum albumin in aqueous (D2O) solutions has been measured comprehensively as a function of the protein and trivalent salt (YCl3) concentration, noted cp and cs, respectively. We observe that D follows a universal master curve D(cs,cp) = D(cs = 0,cp) g(cs/cp), where D(cs = 0,cp) is the diffusion coefficient in the absence of salt

Real-time observation of nonclassical protein crystallization kinetics

We present a real-time study of protein crystallization of bovine-lactoglobulin in the presence of CdCl2 using small-angle X-ray scattering and optical microscopy. From observing the crystallization kinetics, we propose the following multistep crystallization mechanism that is consistent with our data. In the first step, an intermediate phase is formed, followed by the nucleation of crystals withi

Anomalous and anisotropic nanoscale diffusion of hydration water molecules in fluid lipid membranes

We have studied nanoscale diffusion of membrane hydration water in fluid-phase lipid bilayers made of 1,2-dimyristoyl-3-phosphocholine (DMPC) using incoherent quasi-elastic neutron scattering. Dynamics were fit directly in the energy domain using the Fourier transform of a stretched exponential. By using large, 2-dimensional detectors, lateral motions of water molecules and motions perpendicular t

Gold nanoparticles decorated with oligo(ethylene glycol) thiols : Surface charges and interactions with proteins in solution

We have studied oligo(ethylene glycol) (OEG) thiol self-assembled monolayer (SAM) coated gold nanoparticles (AuOEG) and their interactions with proteins in solutions using electrophoretic and dynamic light scattering (ELS and DLS). The results are compared with poly(ethylene glycol) (PEG) thiol coated AuNPs (AuPEG). We show that both AuOEG and AuPEG particles carry a low net negative charge and ar