Poly(HEMA-co-NBMI) Monolithic Cryogel Columns for IgG Adsorption

Supermacroporous poly(2-hydroxyethyl methacrylate-co-1,5-naphthalene bismaleimide) [poly(HEMA-co-NBMI)] monolithic cryogel column was prepared by free radical cryo-copolymerization of HEMA with NBMI as a hydrophobic functional comonomer and N,N′-methylene-bisacrylamide as cross-linker directly in a plastic syringe for adsorption of albumin. The monolithic cryogel contained a continuous polymeric matrix which has interconnected pores of 10–100 μm size. Poly(HEMA-co-NBMI) cryogel was characterized by swelling studies, FTIR and scanning electron microscopy. The equilibrium swelling degree of the poly(HEMA-co-NBMI) cryogel was 10.5 g of H₂O/g dry cryogel. Poly(HEMA-co-NBMI) cryogel was used in the adsorption/desorption of IgG from aqueous solutions. The maximum amount of IgG adsorption from aqueous solution in phosphate buffer was 98.20 mg/g polymer at pH 7.0. The nonspecific adsorption of IgG onto plain poly(HEMA) cryogel was very low (2.79 g/g polymer). It was observed that IgG could be repeatedly adsorbed and desorbed with the poly(HEMA-co-NBMI) cryogel without significant loss of adsorption capacity.     

Synthesis, characterization and aggregation behaviour of novel peripherally tetra-substituted octacationic water soluble metal-free and metallophthalocyanines

In this study, a new phthalonitrile derivative 3 bearing 1,3-bis[3(dimethylamino)phenoxy]propan-2-ol 1, metal-free phthalocyanine (Pc) 4, metallophthalocyanines (MPcs) 5–7 and their quaternized derivatives 4a–7a were synthesized. Metal-free Pc 4 was prepared by cyclotetramerization of phthalonitrile derivate 3 and MPcs 5–7 were synthesized by heating 3 with NiCl₂, CoCl₂ and CuCl₂ in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, respectively. Quaternization of the dimethylamino functionality produced quaternized octacationic water soluble metal-free, Ni, Co and Cu Pcs which were soluble in water, DMF, DMSO. The aggregation behaviour of these compounds were investigated in different concentrations of chloroform for metal-free, Ni, Co and Cu Pcs. The effect of solvents on absorption spectra were studied in various organic solvents. The novel compounds were characterized using IR, ¹H-, ¹³C NMR, UV–vis and MS spectral data.     

Inhibitor design for 3-hydroxy-3-methyl-glutaryl-CoA reductase enzyme; molecular docking and determination of molecular and electronic properties of ligands by density functional theory method

Designing new inhibitors having less side effects is a need which also could reduce cholesterol levels. To fulfill this aim, we have carried out a molecular docking study toward 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase. A set of designed structural derivatives of statin drugs, eight ligands which are used as HIV-1 integrase inhibitor candidates, a set of terpenoids, and ligands downloaded from Zinc15 database were docked to HMG-CoA reductase enzyme which contains atorvastatin in crystal structure. The analysis of docking studies revealed that statin derivative ligands are more appropriate for inhibition of HMG-CoA reductase. To define the contribution of the molecular properties to the binding of ligands to enzyme structure; the highest occupied molecular orbitals-lowest unoccupied molecular orbitals, hardness, electronegativity, and chemical potential properties of ligands have best score in their sets calculated by quantum mechanical tools.     

Crystal Structure and Computational Study of 5-Ethyl-4-(4-Methoxyphenethyl)-4,5-Dihydro-3H-1,2,4-Triazol-3-One and 4-(4-Methoxyphenethyl)-5-Propyl-4,5-Dihydro-3H-1,2,4-Triazol-3-One

Crystallography Reports - Molecular structures of compounds 5-ethyl-4-(4-methoxyphenethyl)-4,5-dihydro-3H-1,2,4-triazol-3-one, (C13H17N3O2) (I) and...     

Anionic water-soluble sulfonated phthalocyanines: microwave-assisted synthesis,aggregation behaviours,electrochemical and in-situ spectroelectrochemical characterisation

In this work, a phthalonitrile derivative bearing p-sulfonylphenoxy group at the 3-position has been synthesised. The water-soluble non-peripherally tetrasubstituted zinc (3) and cobalt (4) phthalocyanines were obtained by cyclotetramerisation of this phthalonitrile derivative in the presence of anhydrous metal salts by microwave irradiation. The compounds have been characterised by using FT-IR, ¹H NMR, UV–Vis and Mass spectrometry (MS) data. The aggregation behaviours of these compounds were investigated in methanol, DMSO, DMF, and water. We have also studied the aggregation behaviours of the phthalocyanine complex 3 in various DMSO/water mixtures. Additionally, the redox properties of the phthalocyanine complexes were examined in dimethylsulfoxide by voltammetry and in situ spectroelectrochemistry. Redox behaviours of the complexes supported the structures of the complexes. Metal and ring-based reductions were observed for 4 and only ring-based electron transfer processes were observed with 3.     

Mathematical models for job-shop scheduling problems with routing and process plan flexibility

As a result of rapid developments in production technologies in recent years, flexible job-shop scheduling problems have become increasingly significant. This paper deals with two NP-hard optimization problems: flexible job-shop scheduling problems (FJSPs) that encompass routing and sequencing sub-problems, and the FJSPs with process plan flexibility (FJSP-PPFs) that additionally include the process plan selection sub-problem. The study is carried out in two steps. In the first step, a mixed-integer linear programming model (MILP-1) is developed for FJSPs and compared to an alternative model in the literature (Model F) in terms of computational efficiency. In the second step, one other mixed-integer linear programming model, a modification of MILP-1, for the FJSP-PPFs is presented along with its computational results on hypothetically generated test problems.     

Strong coupling constants of light pseudoscalar mesons with heavy baryons in QCD

We calculate the strong coupling constants of light pseudoscalar mesons with heavy baryons within the light cone QCD sum rules method. It is shown that sextet–sextet, sextet–antitriplet and antitriplet–antitriplet transitions are described by one universal invariant function for each class. A comparison of our results on the coupling constants with the predictions existing in literature is also presented.     

Discrete-Time Pricing and Optimal Exercise of American Perpetual Warrants in the Geometric Random Walk Model

An American option (or, warrant) is the right, but not the obligation, to purchase or sell an underlying equity at any time up to a predetermined expiration date for a predetermined amount. A perpetual American option differs from a plain American option in that it does not expire. In this study, we solve the optimal stopping problem of a perpetual American option (both call and put) in discrete time using linear programming duality. Under the assumption that the underlying stock price follows a discrete time and discrete state Markov process, namely a geometric random walk, we formulate the pricing problem as an infinite dimensional linear programming (LP) problem using the excessive-majorant property of the value function. This formulation allows us to solve complementary slackness conditions in closed-form, revealing an optimal stopping strategy which highlights the set of stock-prices where the option should be exercised. The analysis for the call option reveals that such a critical value exists only in some cases, depending on a combination of state-transition probabilities and the economic discount factor (i.e., the prevailing interest rate) whereas it ceases to be an issue for the put.     

Multiagent cooperation for solving global optimization problems: an extendible framework with example cooperation strategies

This paper proposes the use of multiagent cooperation for solving global optimization problems through the introduction of a new multiagent environment, MANGO. The strength of the environment lays in its flexible structure based on communicating software agents that attempt to solve a problem cooperatively. This structure allows the execution of a wide range of global optimization algorithms described as a set of interacting operations. At one extreme, MANGO welcomes an individual non-cooperating agent, which is basically the traditional way of solving a global optimization problem. At the other extreme, autonomous agents existing in the environment cooperate as they see fit during run time. We explain the development and communication tools provided in the environment as well as examples of agent realizations and cooperation scenarios. We also show how the multiagent structure is more effective than having a single nonlinear optimization algorithm with randomly selected initial points.