Analysis of Dissipated Power Caused by Lubrication in Ringless Reciprocating Systems

The purpose of this paper was to evaluate the electromotor input power loss caused by oil viscosity between piston and cylinder in reciprocating systems such as compressors, presses and pumps with crank and slider driver without oil ring or ringless pistons. Using the numerical and analytical approaches respectively for nonlinear and linear oil velocity profiles assumed between piston and cylinder, dissipated power caused by oil viscosity was calculated and results of these two approaches were compared to validate finite difference results. Finally, the effect of vertical or horizontal position of piston and cylinder were compared in the case of nonlinear oil velocity profile for different applications

Relative flux trade-offs and optimization of metabolic network functionalities

Trade-offs between traits are present across different levels of biological systems and ultimately reflect constraints imposed by physicochemical laws and the structure of underlying biochemical networks. Yet, mechanistic explanation of how trade-offs between molecular traits arise and how they relate to optimization of fitness-related traits remains elusive. Here, we introduce the concept of relative flux trade-offs and propose a constraint-based approach, termed FluTOr, to identify metabolic reactions whose fluxes are in relative trade-off with respect to an optimized fitness-related cellular task, like growth. We then employed FluTOr to identify relative flux trade-offs in the genome-scale metabolic networks of Escherichia coli, Saccharomyces cerevisiae, and Arabidopsis thaliana. For the metabolic models of E. coli and S. cerevisiae we showed that: (i) the identified relative flux trade-offs depend on the carbon source used and that (ii) reactions that participated in relative trade-offs in both species were implicated in cofactor biosynthesis. In contrast to the two microorganisms, the relative flux trade-offs for the metabolic model of A. thaliana did not depend on the available nitrogen sources, reflecting the differences in the underlying metabolic network as well as the considered environments. Lastly, the established connection between relative flux trade-offs allowed us to identify overexpression targets that can be used to optimize fitness-related traits. Altogether, our computational approach and findings demonstrate how relative flux trade-offs can shape optimization of metabolic tasks, important in biotechnological applications. (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of Research Network of Computational and Structural Biotechnology.Peer reviewe

Genetic algorithm solution for double digest problem

The strongly NP-Hard Double Digest Problem, for reconstructing the physical map of DNA sequence, in now using for efficient genotyping. Most of the existing methods are inefficient in tackling large instances due to the large search space for the problem which grows as a factorial function (a!)(b!) of the numbers a and b of the DNA fragments generated by the two restriction enzymes. Also, none of the existing methods are able to handle the erroneous data. In this paper, we develop a novel method based on genetic algorithm for solving this problem and it is adapted to handle the erroneous data. Our genetic algorithm is implemented and compared with the other well-known existing algorithms. The obtained results show the efficiency (speedup) of our algorithm with respect to the other methods, specially for erroneous data

Subsidization of substance use treatment: Comparison of methadone maintenance treatment and abstinence-based residential treatment in Iran

Background: Subsidization is a policy to encourage the purchase and use of goods and services and to promote their affordability for the poor. The Welfare Organization of Iran subsidizes substance use treatment in order to increase coverage and adherence to treatment. Objectives: This study aimed to answer the following questions: is the model efficient? Has the policy resulted in increased coverage and higher adherence to substance use treatment? How could the model be improved? Methods: We compared two types of substance use treatments of abstinence-based residential program and outpatient methadone maintenance. Based on their severity of addiction and retention in treatment clients who benefited from subsidization were compared with other clients. Therefore, 109 clients, 78 from methadone maintenance and 31 from residential abstinence-based programs were interviewed. Results: Subsidization had an encouraging effect on clients to enter substance use treatment in both treatment programs (P = 0.001). However, we were unable to find evidence that subsidization helped retention in the treatment (P = 0.389), or that concomitant use of illegal substances in clients on methadone maintenance was lower (P = 0.500). Based on economic status of clients (P = 0.05) their criminal record (P = 0.001), length of use of substances (P = 0.05), and comorbid psychiatric conditions (P = 0.05), it was evident that assignment to subsidization in methadone maintenance services was significantly more reasonable, while it was almost random in abstinence-based residential facilities assignment. Conclusions: The current model of substance use treatment subsidization is not efficient. Addiction severity subscales and socioeconomic status of clients could be considered appropriate factors for assignment to the subsidization program. Copyright © 2020, Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/) which permits copy and redistribute the material just in noncommercial usages, provided the original work is properly cited

Razvoj i biofarmaceutsko vrednovanje pripravka za povećano oslobađanje tramadol hidroklorida na principu osmotske tehnologije

Extended release formulation of tramadol hydrochloride (TRH) based on osmotic technology was developed and evaluated. Target release profile was selected and different variables were optimized to achieve the same. Formulation variables like level of swellable polymer, plasticizer and the coat thickness of semipermeable membrane (SPM) were found to markedly affect the drug release. TRH release was directly proportional to the levels of plasticizer but inversely proportional to the levels of swellable polymer and coat thickness of SPM. Drug release from developed formulations was independent of pH and agitation intensity but dependent on osmotic pressure of the release media. In vivo study was also performed on six healthy human volunteers and various pharmacokinetic parameters (cmax, tmax, AUC0-24, MRT) and relative bioavailability were calculated. The in vitro and in vivo results were compared with performance of two commercial tablets of TRH. The developed formulation provided more prolonged and controlled TRH release as compared to marketed formulation. In vitro-in vivo correlation (IVIVC) was analyzed according to Wagner-Nelson method. The optimized formulation (batch IVB) exhibited good IVIV correlation (R = 0.9750). The manufacturing procedure was found to be reproducible and formulations were stable during 6 months of accelerated stability testing.U radu je opisana priprava i evaluacija pripravaka tramadol hidroklorida (TRH) na principu osmotske tehnologije. Da bi se postigao željeni profil oslobađanja mijenjane su različite varijable. Pokazalo se da najveći utjacaj na oslobađanje ljekovite tvari imaju udjeli polimera koji bubri, plastifikatora i debljina ovojnice polupropusne membrane (SPM). TRH oslobađanje bilo je proporcionalno udjelu plastifikatora, a obrnuto proporcionalno udjelu polimera i vrijednosti SPM. Oslobađanje ljekovite tvari bilo je neovisno o pH i intenzitetu miješanja, a ovisno o osmotskom talku medija. U in vivo studiji provedenoj na šest zdravih volontera određeni su farmakokinetički parametri (cmax, tmax, AUC0-24, MRT) i izračunata relativna bioraspoloživost. Rezultati dobiveni u pokusima in vitro i in vivo uspoređeni su s dvije vrste komercijalno dostupnih tableta TRH: oslobađanje ljekovite tvari iz pripravka razvijenog u ovom radu bilo je dulje i više kontrolirano. In vitro-in vivo korelacija (IVIVC) je analizirana prema Wagner-Nelsonovoj metodi. Optimizirani pripravak (IVB) pokazao je dobru IVIV korelaciju (R = 0,9750). Proizvodni proces je bio reproducibilan i pripravci su bili stabilni tijekom 6 mjeseci u uvjetima ubrzanog starenja