Designing Functional Fruit-Based Recovery Drinks in Powder Form That Contain Electrolytes,Peptides, Carbohydrates and Prebiotic Fiber Taking into Account Each Component’s Osmolality

High levels of osmolalities have been found in manufactured carbohydrate-based functional drinks that occasionally include added protein; however, fruit components rich in bioactive ingredients have been absent. It has proved difficult to obtain recovery drinks based on natural fruit components that deliver calories and nutrients to the body whilst simultaneously ensuring that the body is adequately hydrated after physical exertion; the problem being that it is difficult to ensure the drinks’ stability at low pH levels and maintain an appropriate sensory quality. This study aims to develop drinks based on natural fruit components that contain added electrolytes, carbohydrates, prebiotic fiber and protein; an improved water and electrolyte balance; the calories needed after intense physical exertion; a high content of nutrients; and a favorable sensory quality. Furthermore, the relationships between regressive osmolalities of beverage components are herein investigated. The study materials were raspberry powders (prepared via fluidized-bed jet milling, drying, freeze-drying and spray-drying) as well as citrated sodium, potassium, magnesium salts, isomaltulose, hydrolyzed collagen, whey protein isolate and prebiotic fiber. The drinks’ polyphenols and antioxidant properties were measured spectrophotometrically, whilst vitamin C content was determined using high-pressure liquid chromatography. The sensory qualities of each drink were assessed according to a scaling method. Six test versions of recovery drinks were prepared in which osmolalities ranged from 388 to 607 mOsm/kg water, total polyphenol content was 27–49 mg GAE/100 mL and vitamin C level was 8.1–20.6 mg/100 mL, following compositions defined by the study results. It is thus possible to obtain fruit-based recovery drinks of the recommended osmolality that contain added protein, prebiotics and fiber, as well as defined amounts of electrolytes and carbohydrates. All drinks were found to have a satisfactorily sensory quality. The design of appropriate recovery drink compositions was also greatly helped by investigating the relationships among the regressive osmolalities of beverage components (i.e., electrolytes, carbohydrates, fruit powders and protein).     

The Sobolev-type moment problem

We propose necessary and sufficient conditions for a bisequence of complex numbers to be a moment one of Sobolev type over the real line, the unit circle and the complex plane. We achieve this through converting the moment problem in question into a matrix one and utilizing some techniques coming from operator theory. This allows us to consider the Sobolev type moment problem in its full generality, not necessarily in the diagonal case and even of infinite order.     

Editorial for Special Issue on 3D Printing

Transport in Porous Media -     

Logistic equation of arbitrary order

The paper is concerned with the new logistic equation of arbitrary order which describes the performance of complex executive systems X vs. number of tasks N, operating at limited resources K, at non-extensive, heterogeneous self-organization processes characterized by parameter f. In contrast to the classical logistic equation which exclusively relates to the special case of sub-extensive homogeneous self-organization processes at f=1, the proposed model concerns both homogeneous and heterogeneous processes in sub-extensive and super-extensive areas. The parameter of arbitrary order f, where −∞<f<+∞, depends on both the coefficient of external resource utilization u=N/K, where 0<u<1, and the internal microscopic character of realized processes related to the depth of feedback β. The coefficient β directly influences self-organization of processes by the change of microscopic parameters V_i, S_i, i and Z, where V_i is the number of references (visit) to the ith component of the system during the service of each task, S_i is the time of serving the task by the ith component, and Z is the think time of a given process. In the general case of complex system, parameters V_i, S_i, i and Z can have values in the range from 0 to +∞. In this way the new equation includes all possible cases of a complex executive system’s operation. Furthermore, it allows us to define the optimal matching point between X and N with f as the parameter. It also helps to balance the load in complex systems and to equip artificial systems with self-optimization mechanisms similar to those observed in natural systems.     

Assessment of two theoretical methods to estimate potentiometric titration curves of peptides: comparison with experiment

We compared the ability of two theoretical methods of pH-dependent conformational calculations to reproduce experimental potentiometric titration curves of two models of peptides: Ac-K5-NHMe in 95% methanol (MeOH)/5% water mixture and Ac-XX(A)7OO-NH2 (XAO) (where X is diaminobutyric acid, A is alanine, and O is ornithine) in water, methanol (MeOH), and dimethyl sulfoxide (DMSO), respectively. The titration curve of the former was taken from the literature, and the curve of the latter was determined in this work. The first theoretical method involves a conformational search using the electrostatically driven Monte Carlo (EDMC) method with a low-cost energy function (ECEPP/3 plus the SRFOPT surface-solvation model, assumming that all titratable groups are uncharged) and subsequent reevaluation of the free energy at a given pH with the Poisson-Boltzmann equation, considering variable protonation states. In the second procedure, molecular dynamics (MD) simulations are run with the AMBER force field and the generalized Born model of electrostatic solvation, and the protonation states are sampled during constant-pH MD runs. In all three solvents, the first pKa of XAO is strongly downshifted compared to the value for the reference compounds (ethylamine and propylamine, respectively); the water and methanol curves have one, and the DMSO curve has two jumps characteristic of remarkable differences in the dissociation constants of acidic groups. The predicted titration curves of Ac-K5-NHMe are in good agreement with the experimental ones; better agreement is achieved with the MD-based method. The titration curves of XAO in methanol and DMSO, calculated using the MD-based approach, trace the shape of the experimental curves, reproducing the pH jump, while those calculated with the EDMC-based approach and the titration curve in water calculated using the MD-based approach have smooth shapes characteristic of the titration of weak multifunctional acids with small differences between the dissociation constants. Nevertheless, quantitative agreement between theoretically predicted and experimental titration curves is not achieved in all three solvents even with the MD-based approach, which is manifested by a smaller pH range of the calculated titration curves with respect to the experimental curves. The poorer agreement obtained for water than for the nonaqueous solvents suggests a significant role of specific solvation in water, which cannot be accounted for by the mean-field solvation models.     

Synthesis of bicyclic 2,6-diketopiperazines via a three-step sequence involving an Ugi five-center,four-component reaction

A three-step sequence involving an Ugi five-center, four-component reaction (U-5C-4CR), amide N-detertbutylation and cyclocondensation has been developed for easy access to diverse bicyclic 2,6-diketopiperazine (2,6-DKP) derivatives. In the key step, aromatic aldehydes were successfully coupled with cyclic α-amino acids and isocyanides in the course of U-5C-4CR. Boron trifluoride-acetic acid complex was developed as a new N-detertbutylating agent effective at rt.     

Photoinduced CC‐coupling Reactions of Rigid Diastereomeric Benzophenone‐Methionine Dyads

The reactions of ketone/methionine systems are widely used as efficient and selective sources of biorelevant radical species. In this study, we address intramolecular variants of this couple with respect to its photosynthetic utility and as a mechanistic model of underlying elementary reaction steps of biological importance, especially with respect to the study of photoinitiated electron transport in complex peptides. The outcomes of this study are two‐fold: (1) steady‐state irradiation of sterically constrained benzophenone/methionine dyads afforded stable photocyclization products with high yield and product selectivity. (2) Mechanistic insights into the triplet‐triggered product formation were obtained from an analysis of the flash photolysis results and the molecular structure of the stable product formed upon irradiation. Time‐resolved experiments identified (net) hydrogen‐atom transfer from the methionine as the mechanism of the triplet quenching and the resulting biradicals as the major precursor of the isolated stable product. Both the analyses of triplet quenching and stable‐product formation in the diastereomeric pairs point to effects of chiral center configuration, i.e., significant stereoselectivity is observed for all elementary steps. The underlying stereochemical restraints were quantitatively addressed by means of molecular dynamics simulations.     

Coevolutionary-based Mechanisms for Network Anomaly Detection

The paper presents an approach based on the principles of immune systems applied to the anomaly detection problem. Flexibility and efficiency of the anomaly detection system are achieved by building a model of the network behavior based on the self–nonself space paradigm. Covering both self and nonself spaces by hyperrectangular structures is proposed. The structures corresponding to self-space are built using a training set from this space. The hyperrectangular detectors covering nonself space are created using a niching genetic algorithm. A coevolutionary algorithm is proposed to enhance this process. The results of experiments show a high quality of intrusion detection, which outperform the quality of the recently proposed approach based on a hypersphere representation of the self-space.      

Probabilistic model of influenza virus transmissibility at various temperature and humidity conditions

The spread efficiency of influenza virus is significantly affected by several environmental parameters. However, neither the underlying reasons, nor the exact character and magnitude of the phenomena involved are sufficiently well understood. Here we present a probabilistic approach to the virus transmission events. For a sample ensemble, we construct a model of the infectivity as a function of the ambient conditions, and we determine its parameter values on the basis of the available experimental data.     

Adjoints and formal adjoints of matrices of unbounded operators

In this paper we discuss diverse aspects of the mutual relationship between adjoints and formal adjoints of unbounded operators bearing a matrix structure. We emphasize the behaviour of row and column operators as they turn out to be the germs of an arbitrary matrix operator, providing most of the information about the latter as it is the troublemaker.