Energy-efficient node position identification through payoff matrix and variability analysis

This paper investigates the use of punctured recursive systematic convolutional codes for turbo coding in a 2-user binary adder channel (2-BAC) in the presence of additive white Gaussian noise, aiming to achieve a higher transmission sum rate with reduced decoding complexity. The encoders for the 2-BAC are assumed to be block synchronized and to employ identical puncturing patterns. Iterative decoding combining the Bahl Cocke Jelinek Raviv algorithm and a two-user punctured trellis is employed. For each user and for a fixed puncturing pattern, random interleavers of length 256 bits or 1024 bits, respectively, are simulated and corresponding curves relating bit error rate versus signal to noise ratio are presented for performance comparison purposes. Computer simulation indicates that the loss in performance of a punctured turbo code can be negligible when longer interleavers are used for both users, similarly to the single user case.     

Factors affecting the solid-state structure and dimensionality of mercury cyanide/chloride double salts, and NMR characterization of coordination geometries

In the reaction of organic monocationic chlorides or coordinatively saturated metal-ligand complex chlorides with linear, neutral Hg(CN)(2) building blocks, the Lewis-acidic Hg(CN)(2) moieties accept the chloride ligands to form mercury cyanide/chloride double salt anions that in several cases form infinite 1-D and 2-D arrays. Thus, [PPN][Hg(CN)(2)Cl].H(2)O (1), [(n)Bu(4)N][Hg(CN)(2)Cl].0.5 H(2)O (2), and [Ni(terpy)(2)][Hg(CN)(2)Cl](2) (4) contain [Hg(CN)(2)Cl](2)(2-) anionic dimers ([PPN]Cl = bis(triphenylphosphoranylidene)ammonium chloride, [(n)Bu(4)N]Cl = tetrabutylammonium chloride, terpy = 2,2':6',6' '-terpyridine). [Cu(en)(2)][Hg(CN)(2)Cl](2) (5) is composed of alternating 1-D chloride-bridged [Hg(CN)(2)Cl](n)(n-) ladders and cationic columns of [Cu(en)(2)](2+) (en = ethylenediamine). When [Co(en)(3)]Cl(3) is reacted with 3 equiv of Hg(CN)(2), 1-D [[Hg(CN)(2)](2)Cl](n)(n-) ribbons and [Hg(CN)(2)Cl(2)](2-) moieties are formed; both form hydrogen bonds to [Co(en)(3)](3+) cations, yielding [Co(en)(3)][Hg(CN)(2)Cl(2)][[Hg(CN)(2)](2)Cl] (6). In [Co(NH(3))(6)](2)[Hg(CN)(2)](5)Cl(6).2H(2)O (7), [Co(NH(3))(6)](3+) cations and water molecules are sandwiched between chloride-bridged 2-D anionic [[Hg(CN)(2)](5)Cl(6)](n)(6n-) layers, which contain square cavities. The presence (or absence), number, and profile of hydrogen bond donor sites of the transition metal amine ligands were observed to strongly influence the structural motif and dimensionality adopted by the anionic double salt complex anions, while cation shape and cation charge had little effect. (199)Hg chemical shift tensors and (1)J((13)C,(199)Hg) values measured in selected compounds reveal that the NMR properties are dominated by the Hg(CN)(2) moiety, with little influence from the chloride bonding characteristics. delta(iso)((13)CN) values in the isolated dimers are remarkably sensitive to the local geometry.     

In Silico Evaluation of the Antimicrobial Activity of Thymol—Major Compounds in the Essential Oil of Lippia thymoides Mart. & Schauer (Verbenaceae)

In this paper, we evaluated the drug-receptor interactions responsible for the antimicrobial activity of thymol, the major compound present in the essential oil (EO) of Lippia thymoides (L. thymoides) Mart. & Schauer (Verbenaceae). It was previously reported that this EO exhibits antimicrobial activity against Candida albicans (C. albicans), Staphylococcus aureus (S. aureus), and Escherichia coli (E. coli). Therefore, we used molecular docking, molecular dynamics simulations, and free energy calculations to investigate the interaction of thymol with pharmacological receptors of interest to combat these pathogens. We found that thymol interacted favorably with the active sites of the microorganisms’ molecular targets. MolDock Score results for systems formed with CYP51 (C. albicans), Dihydrofolate reductase (S. aureus), and Dihydropteroate synthase (E. coli) were −77.85, −67.53, and −60.88, respectively. Throughout the duration of the MD simulations, thymol continued interacting with the binding pocket of the molecular target of each microorganism. The van der Waals (ΔE_vdW = −24.88, −26.44, −21.71 kcal/mol, respectively) and electrostatic interaction energies (ΔE_ele = −3.94, −11.07, −12.43 kcal/mol, respectively) and the nonpolar solvation energies (ΔG_NP = −3.37, −3.25, −2.93 kcal/mol, respectively) were mainly responsible for the formation of complexes with CYP51 (C. albicans), Dihydrofolate reductase (S. aureus), and Dihydropteroate synthase (E. coli).     

Phytochemical Analysis,Antibacterial Activity and Modulating Effect of Essential Oil from Syzygium cumini (L.) Skeels

One of the main global problems that affect human health is the development of bacterial resistance to different drugs. As a result, the growing number of multidrug-resistant pathogens has contributed to an increase in resistant infections and represents a public health problem. The present work seeks to investigate the chemical composition and antibacterial activity of the essential oil of Syzygium cumini leaves. To identify its chemical composition, gas chromatography coupled to mass spectrometry was used. The antibacterial activity test was performed with the standard strains Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 25853 and Staphylococcus aureus ATCC 25923 and multidrug-resistant clinical isolates E. coli 06, P. aeruginosa 24 and S. aureus 10. The minimum inhibitory concentration (MIC) was determined by serial microdilution as well as the verification of the modulating effect of the antibiotic effect. In this test, the oil was used in a subinhibitory concentration. The test reading was performed after 24 h of incubation at 37 °C. The results show that the major chemical constituent is α-pinene (53.21%). The oil showed moderate activity against E. coli ATCC 25922, with the MIC of 512 µg/mL; there was no activity against the other strains. The oil potentiated the effect of antibiotics demonstrating possible synergism when associated with gentamicin, erythromycin and norfloxacin against E. coli 06 and S. aureus 10.     

New Insights on Glutathione’s Supramolecular Arrangement and Its In Silico Analysis as an Angiotensin-Converting Enzyme Inhibitor

Angiotensin-converting enzyme (ACE) inhibitors are one of the most active classes for cardiovascular diseases and hypertension treatment. In this regard, developing active and non-toxic ACE inhibitors is still a continuous challenge. Furthermore, the literature survey shows that oxidative stress plays a significant role in the development of hypertension. Herein, glutathione’s molecular structure and supramolecular arrangements are evaluated as a potential ACE inhibitor. The tripeptide molecular modeling by density functional theory, the electronic structure by the frontier molecular orbitals, and the molecular electrostatic potential map to understand the biochemical processes inside the cell were analyzed. The supramolecular arrangements were studied by Hirshfeld surfaces, quantum theory of atoms in molecules, and natural bond orbital analyses. They showed distinct patterns of intermolecular interactions in each polymorph, as well as distinct stabilizations of these. Additionally, the molecular docking study presented the interactions between the active site residues of the ACE and glutathione via seven hydrogen bonds. The pharmacophore design indicated that the hydrogen bond acceptors are necessary for the interaction of this ligand with the binding site. The results provide useful information for the development of GSH analogs with higher ACE inhibitor activity.     

Essential Oil of the Plants Growing in the Brazilian Amazon: Chemical Composition,Antioxidants, and Biological Applications

Essential oils are biosynthesized in the secondary metabolism of plants, and in their chemical composition, they can be identified different classes of compounds with potential antioxidant and biological applications. Over the years in the Amazon, several species of aromatic plants were discovered and used in traditional medicine. The literature has shown that essential oils extracted from amazon species have several biological activities, such as antioxidant, antibacterial, antifungal, cytotoxic, and antiprotozoal activities. These activities are related to the diversified chemical composition found in essential oils that, by synergism, favors its pharmacological action. In light of this vital importance, this study aimed at performing a review of the literature with particular emphasis on the chemical composition and biological activities in studies conducted with species collected in the Amazon, taking into consideration in particular the last 10 years of collection and research.     

Simultaneous Determination of Caffeine,Ibuprofen, and Paracetamol by Flow‐injection Analysis with Multiple‐pulse Amperometric Detection on Boron‐doped Diamond Electrode

This work presents a simple, fast and low‐cost method for the simultaneous determination of three drugs by flow‐injection analysis with multiple‐pulse amperometric (MPA) detection using a wall‐jet flow cell with a boron‐doped diamond electrode. The amperometric determination of caffeine (CF), ibuprofen (IB) and paracetamol (PC) was performed by the application of a four‐potential waveform using the MPA technique. PC is oxidized at E₁ (1.20 V/70 ms) and thus selectively detected; PC and CF are oxidized at E₂ (1.49 V/40 ms); PC, CF and IB are oxidized at E₃ (1.70 V/70 ms); and E₄ (1.80 V/100 ms) is applied for electrode cleaning. The subtraction of currents obtained at the different potentials did not provide accurate determinations of CF and IB, thus it was required to investigate correction factors to determine CF and IB without the interference from PC and CF using the respective amperometric signals obtained at E₂ and E₃. The proposed method was successfully applied for the determination of three drugs in pharmaceutical samples with low generation of residues and a high analytical frequency (150 h^?1) in comparison with HPLC‐DAD method.     

Tucumã (Astrocaryum vulgare) fat: an Amazonian material as a pharmaceutical input for lipid nanoparticle production

Journal of Thermal Analysis and Calorimetry - Native Amazon palm trees have been target of research and product development especially because of their oil and fat. Tucumã-do-Pará...