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1

Wojnárovits, László, and Erzsébet Takács. "Rate constants of dichloride radical anion reactions with molecules of environmental interest in aqueous solution: a review." Environmental Science and Pollution Research 28, no. 31 (June 4, 2021): 41552–75. http://dx.doi.org/10.1007/s11356-021-14453-w.

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AbstractNatural waters, water droplets in the air at coastal regions and wastewaters usually contain chloride ions (Cl-) in relatively high concentrations in the milimolar range. In the reactions of highly oxidizing radicals (e.g., •OH, •NO3, or SO4•-) in the nature or during wastewater treatment in advanced oxidation processes the chloride ions easily transform to chlorine containing radicals, such as Cl•, Cl2•-, and ClO•. This transformation basically affects the degradation of organic molecules. In this review about 400 rate constants of the dichloride radical anion (Cl2•-) with about 300 organic molecules is discussed together with the reaction mechanisms. The reactions with phenols, anilines, sulfur compounds (with sulfur atom in lower oxidation state), and molecules with conjugated electron systems are suggested to take place with electron transfer mechanism. The rate constant is high (107–109 M-1 s-1) when the reduction potential the one-electron oxidized species/molecule couple is well below that of the Cl2•-/2Cl- couple.
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2

Avramenko, Aleksandr G. "Chemical applications of hybridized light-matter states (a review)." Voprosy Khimii i Khimicheskoi Tekhnologii, no. 4 (July 2023): 3–16. http://dx.doi.org/10.32434/0321-4095-2023-149-4-3-16.

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Interactions between light and matter are a fundamental part of chemical sciences responsible for basic photophysical processes such as phosphorescence and fluorescence. However, these photophysical phenomena occur in the "weak" limit of interaction between light and matter in which the photon and molecule interact with each other without the former fundamentally changing the physical properties of the latter. By constructing a Fabry-Perot cavity, which traps light of a certain frequency, then placing a molecule in a cavity that undergoes a molecular electron transition at the frequency of the trapped light, scientists can force strong light-matter interaction. This interaction occurs if the exchange between the light of the cavity mode and the molecule's excited state is faster than the decay rate of either state, forming a hybrid light-matter state known as a polariton. The photophysical properties of these polariton states have been of interest to scientists due to the possibility that they can allow for the modification of the reactivity of molecules without the addition of functional groups or modification of the surrounding environment. Of particular interest is the ability of polaritons to influence the potential energy surface of molecules, with polaritons showing the ability to both, suppress the photochemical reaction in molecules such as spiropyran and stilbene, while also enhancing the nonradiative relaxation rate of porphyrins. Due to their photonic nature, polaritons have also shown the ability to facilitate long range energy transfer processes in organic dye molecules. This review focuses on discussing these recent advances in a chemistry context as well as the optical design of cavities required to sustain polaritons.
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Casey, William H. "Ligand- and oxygen-isotope-exchange pathways of geochemical interest." Environmental Chemistry 12, no. 1 (2015): 1. http://dx.doi.org/10.1071/en14043.

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Environmental context Most chemical processes in water are either ligand- or electron-exchange reactions. Here the general reactivity trends for ligand-exchange reactions in aqueous solutions are reviewed and it is shown that simple rules dominate the chemistry. These simple rules shed light on most molecular processes in water, including the uptake and degradation of pesticides, the sequestration of toxic metals and the corrosion of minerals. Abstract It is through ligand-exchange kinetics that environmental geochemists establish an understanding of molecular processes, particularly for insulating oxides where there are not explicit electron exchanges. The substitution of ligands for terminal functional groups is relatively insensitive to small changes in structure but are sensitive to bond strengths and acid–base chemistry. Ligand exchanges involving chelating organic molecules are separable into two classes: (i) ligand substitutions that are enhanced by the presence of the chelating ligand, called a ‘spectator’ ligand and (ii) chelation reactions themselves, which are controlled by the Lewis basicity of the attacking functional group and the rates of ring closure. In contrast to this relatively simple chemistry at terminal functional groups, substitutions at bridging oxygens are exquisitely sensitive to details of structure. Included in this class are oxygen-isotope exchange and mineral-dissolution reactions. In large nanometer-sized ions, metastable structures form as intermediates by detachment of a surface metal atom, often from a underlying, highly coordinated oxygen, such as μ4-oxo, by solvation forces. A metastable equilibrium is then established by concerted motion of many atoms in the structure. The newly undercoordinated metal in the intermediate adds a water or ligand from solution, and protons transfer to other oxygens in the metastable structure, giving rise to a characteristic broad amphoteric chemistry. These metastable structures have an appreciable lifetime and require charge separation, which is why counterions affect the rates. The number and character of these intermediate structures reflect the symmetry of the starting structure.
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4

Wojnárovits, László, Tünde Tóth, and Erzsébet Takács. "Rate constants of carbonate radical anion reactions with molecules of environmental interest in aqueous solution: A review." Science of The Total Environment 717 (May 2020): 137219. http://dx.doi.org/10.1016/j.scitotenv.2020.137219.

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5

Correale, Jorge, and Mauricio F. Farez. "The impact of environmental infections (parasites) on MS activity." Multiple Sclerosis Journal 17, no. 10 (October 2011): 1162–69. http://dx.doi.org/10.1177/1352458511418027.

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MS incidence has significantly increased during the second half of the 20th century, generating considerable interest in analyzing the basis for this rise in the developed world. Particular emphasis is being placed on the role infections might play in exacerbating or preventing disease onset. Epidemiological data suggest that improvement in sanitation conditions and reduced exposure to infection might explain, at least in part, these changes. The hygiene hypothesis is not new and is currently used to explain the increasing incidence of allergies and other autoimmune diseases. Because helminths are powerful modulators of host immunity, some authors hypothesize that reduced parasite exposure due to improved hygiene conditions may favor MS development. We discuss epidemiological, experimental, clinical and molecular data supporting the protective role of helminthes against MS. Better understanding of host–parasite interactions caused by specific parasite molecules with immunomodulatory effects will help combat allergies and autoimmune disease without the price of untoward infection as a side-effect.
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6

Nie, Nan, Xin Zhang, Chu Fang, Qiu Zhu, Jiao Lu, Fu Zhang, Qing Yao, Wei Huang, Xue Ding, and Li Xia. "Game Theory in Molecular Nanosensing System for Rapid Detection of Hg2+ in Aqueous Solutions." Applied Sciences 8, no. 12 (December 7, 2018): 2530. http://dx.doi.org/10.3390/app8122530.

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Game theory—the scientific study of interactive, rational decision making—describes the interaction of two or more players from macroscopic organisms to microscopic cellular and subcellular levels. Life based on molecules is the highest and most complex expression of molecular interactions. However, using simple molecules to expand game theory for molecular decision-making remains challenging. Herein, we demonstrate a proof-of-concept molecular game-theoretical system (molecular prisoner’s dilemma) that relies on formation of the thymine–Hg2+–thymine hairpin structure specifically induced by Hg2+ and fluorescence quenching and molecular adsorption capacities of cobalt oxyhydroxide (CoOOH) nanosheets, resulting in fluorescence intensity and distribution change of polythymine oligonucleotide 33-repeat thymines (T33). The “bait” molecule, T33, interacted with two molecular players, CoOOH and Hg2+, in different states (absence = silence and presence = betrayal), regarded as strategies. We created conflicts (sharing or self-interest) of fluorescence distribution of T33, quantifiable in a 2 × 2 payoff matrix. In addition, the molecular game-theoretical-system based on T33 and CoOOH was used for sensing Hg2+ over the range of 20 to 600 nM with the detection limit of 7.94 nM (3σ) and for determination of Hg2+ in pond water. Inspired by the proof-of-concept for molecular game theory, various molecular decision-making systems could be developed, which would help promote molecular information processing and generating novel molecular intelligent decision systems for environmental monitoring and molecular diagnosis and therapy.
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7

SHANKARAN, D., K. GOBI, and N. MIURA. "Recent advancements in surface plasmon resonance immunosensors for detection of small molecules of biomedical, food and environmental interest." Sensors and Actuators B: Chemical 121, no. 1 (January 30, 2007): 158–77. http://dx.doi.org/10.1016/j.snb.2006.09.014.

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8

Minati, L., G. Speranza, I. Bernagozzi, S. Torrengo, L. Toniutti, B. Rossi, M. Ferrari, and A. Chiasera. "Synthesis of Carbon Nanotubes/Gold Nanoparticles Hybrids for Environmental Applications." Advances in Science and Technology 71 (October 2010): 34–39. http://dx.doi.org/10.4028/www.scientific.net/ast.71.34.

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Multi-walled carbon nanotubes were chemically cut by acid treatments and then deposited on 2-aminoethanethiol-modified gold substrate by the application of an external electric field. 2-aminoethanethiol-capped gold nanoparticles were then covalently bonded to the nanotubes to exploit their plasmon resonances. Reaction intermediates as well as the final products were analyzed by X-Ray Photoelectron Spectroscopy, Atomic Force Microscopy and Scanning Electron Microscopy. The synergetic interaction between carbon nanotubes and gold nanoparticles leads to an efficient signal enhancement in Raman spectra. This is of particular interest for the detection of toxic molecules dangerous for the environment.
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9

Bacon, Stuart L., Andrew J. Daugulis, and J. Scott Parent. "Isobutylene-rich imidazolium ionomers for use in two-phase partitioning bioreactors." Green Chemistry 18, no. 24 (2016): 6586–95. http://dx.doi.org/10.1039/c6gc02251k.

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Imidazolium ionomer derivatives of an isobutylene-rich elastomer demonstrated superior absorption characteristics for target molecules of biological interest compared to their non-ionic parent material, while retaining biocompatibility with a range of suspended cell cultures.
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10

Zhou, Qingqing, Zhigang Xu, and Zhimin Liu. "Molecularly Imprinting–Aptamer Techniques and Their Applications in Molecular Recognition." Biosensors 12, no. 8 (July 29, 2022): 576. http://dx.doi.org/10.3390/bios12080576.

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Molecular imprinting–aptamer techniques exhibit the advantages of molecular imprinting and aptamer technology. Hybrids of molecularly imprinted polymer–aptamer (MIP–aptamer) prepared by this technique have higher stability, binding affinity and superior selectivity than conventional molecularly imprinted polymers or aptamers. In recent years, molecular imprinting–aptamer technologies have attracted considerable interest for the selective recognition of target molecules in complex sample matrices and have been used in molecular recognition such as antibiotics, proteins, viruses and pesticides. This review introduced the development of molecular imprinting–aptamer-combining technologies and summarized the mechanism of MIP–aptamer formation. Meanwhile, we discussed the challenges in preparing MIP–aptamer. Finally, we summarized the application of MIP–aptamer to the molecular recognition in disease diagnosis, environmental analysis, food safety and other fields.
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11

Pagano, Cristina, Giovanna Navarra, Laura Coppola, Beatrice Savarese, Giorgio Avilia, Antonella Giarra, Giovanni Pagano, et al. "Impacts of Environmental Pollution on Brain Tumorigenesis." International Journal of Molecular Sciences 24, no. 5 (March 6, 2023): 5045. http://dx.doi.org/10.3390/ijms24055045.

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Pollutants consist of several components, known as direct or indirect mutagens, that can be associated with the risk of tumorigenesis. The increased incidence of brain tumors, observed more frequently in industrialized countries, has generated a deeper interest in examining different pollutants that could be found in food, air, or water supply. These compounds, due to their chemical nature, alter the activity of biological molecules naturally found in the body. The bioaccumulation leads to harmful effects for humans, increasing the risk of the onset of several pathologies, including cancer. Environmental components often combine with other risk factors, such as the individual genetic component, which increases the chance of developing cancer. The objective of this review is to discuss the impact of environmental carcinogens on modulating the risk of brain tumorigenesis, focusing our attention on certain categories of pollutants and their sources.
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12

Kaur, Ajaypal, Komal Pandey, Ramandeep Kaur, Nisha Vashishat, and Manpreet Kaur. "Nanocomposites of Carbon Quantum Dots and Graphene Quantum Dots: Environmental Applications as Sensors." Chemosensors 10, no. 9 (September 15, 2022): 367. http://dx.doi.org/10.3390/chemosensors10090367.

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Carbon-based quantum dots and their nanocomposites have sparked immense interest for researchers as sensors due to their attractive physico-chemical properties caused by edge effects and quantum confinement. In this review article, we have discussed the synthesis and application of nanocomposites of graphene quantum dots (GQDs) and carbon quantum dots (CQDs). Different synthetic strategies for CQDs, GQDs, and their nanocomposites, are categorized as top-down and bottom-up approaches which include laser ablation, arc-discharge, chemical oxidation, ultrasonication, oxidative cleavage, microwave synthesis, thermal decomposition, solvothermal or hydrothermal method, stepwise organic synthesis, carbonization from small molecules or polymers, and impregnation. A comparison of methodologies is presented. The environmental application of nanocomposites of CQDs/GQDs and pristine quantum dots as sensors are presented in detail. Their applications envisage important domains dealing with the sensing of pollutant molecules. Recent advances and future perspective in the use of CQDs, GQDs, and their nanocomposites as sensors are also explored.
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13

MIHAILOVIĆ, DRAGUTIN T., MIRKO BUDINČEVIĆ, IGOR BALAŽ, and ANJA MIHAILOVIĆ. "STABILITY OF INTERCELLULAR EXCHANGE OF BIOCHEMICAL SUBSTANCES AFFECTED BY VARIABILITY OF ENVIRONMENTAL PARAMETERS." Modern Physics Letters B 25, no. 32 (November 21, 2011): 2407–17. http://dx.doi.org/10.1142/s0217984911027431.

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Communication between cells is realized by exchange of biochemical substances. Due to internal organization of living systems and variability of external parameters, the exchange is heavily influenced by perturbations of various parameters at almost all stages of the process. Since communication is one of essential processes for functioning of living systems it is of interest to investigate conditions for its stability. Using previously developed simplified model of bacterial communication in a form of coupled difference logistic equations we investigate stability of exchange of signaling molecules under variability of internal and external parameters.
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14

Haro-Reyes, Tammy, Lucero Díaz-Peralta, Arturo Galván-Hernández, Anahi Rodríguez-López, Lourdes Rodríguez-Fragoso, and Iván Ortega-Blake. "Polyene Antibiotics Physical Chemistry and Their Effect on Lipid Membranes; Impacting Biological Processes and Medical Applications." Membranes 12, no. 7 (June 30, 2022): 681. http://dx.doi.org/10.3390/membranes12070681.

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This review examined a collection of studies regarding the molecular properties of some polyene antibiotic molecules as well as their properties in solution and in particular environmental conditions. We also looked into the proposed mechanism of action of polyenes, where membrane properties play a crucial role. Given the interest in polyene antibiotics as therapeutic agents, we looked into alternative ways of reducing their collateral toxicity, including semi-synthesis of derivatives and new formulations. We follow with studies on the role of membrane structure and, finally, recent developments regarding the most important clinical applications of these compounds.
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15

Najar, Adel M., Ruwida M. K. Omar, Eman Bobtaina, Salem Jabber, Najwa Mohamed, Tahani Aeyad, Salha M. Tawati, and Aliaa M. M. Khalifa. "Design, Synthesis, Pharmacological Evaluation and DFT Investigation of New Bioactive Unsymmetrical Bi-Functional Ligand." Journal of Drug Delivery and Therapeutics 12, no. 4 (July 15, 2022): 73–80. http://dx.doi.org/10.22270/jddt.v12i4.5429.

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Compounds with more than one bioactive motif become of great interest. In this regard, a new tridentate 1,2-unsymmetrical ligand consists of flexible and rigid bioactive arms spaced by benzene ring in an ortho position designed to form a bifunctional molecule. The 2-((3-(pyridin-2-yl)-1H-pyrazol-1-yl)methyl)benzonitrile (PPMB) synthesized under phase transfer reaction and characterized using 1H-NMR and mass spectroscopy and studied as potent kinase inhibitors. Theoretically, the molecule structure was investigated at the B3LYP/6-311++G(d,p) level of theory in the gas phase and revealed that all bond lengths and bond angles within the accepted limit. The frontier molecular orbitals (FMO) energies (HOMO and LUMO), energy gap, dipole moment, chemical softness and chemical hardness were calculated. Pharmacologically, the ligand activity was investigated in silico using SWISS ADME. Furthermore, the compound was docked into the transforming growth factor (TGF) beta type I receptor kinase active site to evaluate the ability of ligand as a kinase inhibitor. Keywords: DFT, pyrazolyl-pyridine, physiochemical, properties molecular docking, bioactive molecules, unsymmetrical ligands
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16

Traeger, Hanna, Alyssa Ghielmetti, Yoshimitsu Sagara, Stephen Schrettl, and Christoph Weder. "Supramolecular Rings as Building Blocks for Stimuli-Responsive Materials." Gels 8, no. 6 (June 3, 2022): 350. http://dx.doi.org/10.3390/gels8060350.

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Stimuli-responsive polymers are of great interest due to their ability to translate changing environmental conditions into responses in defined materials. One possibility to impart such behavior is the incorporation of optically active molecules into a polymer host. Here, we describe how sensor molecules that consist of a πextended benzothiadiazole emitter and a naphthalene diimide quencher can be exploited in this context. The two optically active entities were connected via different spacers and, thanks to attractive intramolecular interactions between them, the new sensor molecules assembled into cyclic structures in which the fluorescence was quenched by up to 43% when compared to solutions of the individual dyes. Detailed spectroscopic investigations of the sensor molecules in solution show that the extent of donor/acceptor interactions is influenced by various factors, including solvent polarity and ion concentration. The new sensor molecule was covalently incorporated into a polyurethane; the investigation of the optical characteristics in both the solid and solvent-swollen states indicates that a stimulus-induced formation of associated dye pairs is possible in polymeric materials. Indeed, a solvatochromic quenching effect similar to the behavior in solution was observed for solvent-swollen polymer samples, leading to an effective change of the green emission color of the dye to a yellow color.
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17

Aloisi, Iris, Chiara Piccini, Giampiero Cai, and Stefano Del Duca. "Male Fertility under Environmental Stress: Do Polyamines Act as Pollen Tube Growth Protectants?" International Journal of Molecular Sciences 23, no. 3 (February 7, 2022): 1874. http://dx.doi.org/10.3390/ijms23031874.

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Although pollen structure and morphology evolved toward the optimization of stability and fertilization efficiency, its performance is affected by harsh environmental conditions, e.g., heat, cold, drought, pollutants, and other stressors. These phenomena are expected to increase in the coming years in relation to predicted environmental scenarios, contributing to a rapid increase in the interest of the scientific community in understanding the molecular and physiological responses implemented by male gametophyte to accomplish reproduction. Here, after a brief introduction summarizing the main events underlying pollen physiology with a focus on polyamine involvement in its development and germination, we review the main effects that environmental stresses can cause on pollen. We report the most relevant evidence in the literature underlying morphological, cytoskeletal, metabolic and signaling alterations involved in stress perception and response, focusing on the final stage of pollen life, i.e., from when it hydrates, to pollen tube growth and sperm cell transport, with these being the most sensitive to environmental changes. Finally, we hypothesize the molecular mechanisms through which polyamines, well-known molecules involved in plant development, stress response and adaptation, can exert a protective action against environmental stresses in pollen by decoding the essential steps and the intersection between polyamines and pollen tube growth mechanisms.
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18

Le, X. Chris, Victor Pavski, and Hailin Wang. "2002 W.A.E. McBryde Award Lecture — Affinity recognition, capillary electrophoresis, and laser-induced fluorescence polarization for ultrasensitive bioanalysis." Canadian Journal of Chemistry 83, no. 3 (March 1, 2005): 185–94. http://dx.doi.org/10.1139/v04-175.

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The combination of affinity recognition, capillary electrophoresis (CE), laser-induced fluorescence (LIF), and fluorescence polarization for the ultrasensitive determination of compounds of biological interest is described. Competitive immunoassays using CE–LIF eliminate the need for fluorescently labeling trace analytes of interest and are particularly useful for determination of small molecules, such as cyclosporine, gentamicin, vancomycin, and digoxin. Fluorescence polarization allows for differentiation of the antibody-bound from the unbound small molecules. Noncompetitive affinity CE–LIF assays are shown to be highly effective in the determination of biomarkers for DNA damage and HIV-1 infection. An antibody (or aptamer) is used as a fluorescent probe to bind with a target DNA adduct (or the reverse transcriptase of the HIV-1 virus), with the fluorescent reaction products being separated by CE and detected by LIF. Aptamers are attractive affinity probes for protein analysis because of high affinity, high specificity, and the potential for a wide range of target proteins. Fluorescence polarization provides unique information for studying molecular interactions. Innovative integrations of these technologies will have broad applications ranging from cancer research, to biomedical diagnosis, to pharmaceutical and environmental analyses.Key words: capillary electrophoresis, laser-induced fluorescence, fluorescence polarization, immunoassay, affinity probes, antibodies, aptamers, DNA damage, toxins, therapeutic drugs.
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19

Kundu, Karishma, Roberta Teta, Germana Esposito, Mariano Stornaiuolo, and Valeria Costantino. "A Four-Step Platform to Optimize Growth Conditions for High-Yield Production of Siderophores in Cyanobacteria." Metabolites 13, no. 2 (January 20, 2023): 154. http://dx.doi.org/10.3390/metabo13020154.

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In response to Iron deprivation and in specific environmental conditions, the cyanobacteria Anabaena flos aquae produce siderophores, iron-chelating molecules that in virtue of their interesting environmental and clinical applications, are recently gaining the interest of the pharmaceutical industry. Yields of siderophore recovery from in vitro producing cyanobacterial cultures are, unfortunately, very low and reach most of the times only analytical quantities. We here propose a four-step experimental pipeline for a rapid and inexpensive identification and optimization of growth parameters influencing, at the transcriptional level, siderophore production in Anabaena flos aquae. The four-steps pipeline consists of: (1) identification of the promoter region of the operon of interest in the genome of Anabaena flos aquae; (2) cloning of the promoter in a recombinant DNA vector, upstream the cDNA coding for the Green Fluorescent Protein (GFP) followed by its stable transformation in Escherichia Coli; (3) identification of the environmental parameters affecting expression of the gene in Escherichia coli and their application to the cultivation of the Anabaena strain; (4) identification of siderophores by the combined use of high-resolution tandem mass spectrometry and molecular networking. This multidisciplinary, sustainable, and green pipeline is amenable to automation and is virtually applicable to any cyanobacteria, or more in general, to any microorganisms.
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20

Lafumat, Bénédicte, Christoph Mueller-Dieckmann, Gordon Leonard, Nathalie Colloc'h, Thierry Prangé, Thierry Giraud, Fabien Dobias, Antoine Royant, Peter van der Linden, and Philippe Carpentier. "Gas-sensitive biological crystals processed in pressurized oxygen and krypton atmospheres: deciphering gas channels in proteins using a novel `soak-and-freeze' methodology." Journal of Applied Crystallography 49, no. 5 (August 16, 2016): 1478–87. http://dx.doi.org/10.1107/s1600576716010992.

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Molecular oxygen (O2) is a key player in many fundamental biological processes. However, the combination of the labile nature and poor affinity of O2 often makes this substrate difficult to introduce into crystals at sufficient concentrations to enable protein/O2 interactions to be deciphered in sufficient detail. To overcome this problem, a gas pressure cell has been developed specifically for the `soak-and-freeze' preparation of crystals of O2-dependent biological molecules. The `soak-and-freeze' method uses high pressure to introduce oxygen molecules or krypton atoms (O2 mimics) into crystals which, still under high pressure, are then cryocooled for X-ray data collection. Here, a proof of principle of the gas pressure cell and the methodology developed is demonstrated with crystals of enzymes (lysozyme, thermolysin and urate oxidase) that are known to absorb and bind molecular oxygen and/or krypton. The successful results of these experiments lead to the suggestion that the soak-and-freeze method could be extended to studies involving a wide range of gases of biological, medical and/or environmental interest, including carbon monoxide, ethylene, methane and many others.
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21

Huynh, Nina, Emilie Caupos, Caroline Soares Peirera, Julien Le Roux, Adèle Bressy, and Régis Moilleron. "Evaluation of Sample Preparation Methods for Non-Target Screening of Organic Micropollutants in Urban Waters Using High-Resolution Mass Spectrometry." Molecules 26, no. 23 (November 23, 2021): 7064. http://dx.doi.org/10.3390/molecules26237064.

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Non-target screening (NTS) has gained interest in recent years for environmental monitoring purposes because it enables the analysis of a large number of pollutants without predefined lists of molecules. However, sample preparation methods are diverse, and few have been systematically compared in terms of the amount and relevance of the information obtained by subsequent NTS analysis. The goal of this work was to compare a large number of sample extraction methods for the unknown screening of urban waters. Various phases were tested for the solid-phase extraction of micropollutants from these waters. The evaluation of the different phases was assessed by statistical analysis based on the number of detected molecules, their range, and physicochemical properties (molecular weight, standard recoveries, polarity, and optical properties). Though each cartridge provided its own advantages, a multilayer cartridge combining several phases gathered more information in one single extraction by benefiting from the specificity of each one of its layers.
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Barsanti, Laura, Lorenzo Birindelli, and Paolo Gualtieri. "Paramylon and Other Bioactive Molecules in Micro and Macroalgae." International Journal of Molecular Sciences 23, no. 15 (July 27, 2022): 8301. http://dx.doi.org/10.3390/ijms23158301.

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Many algae synthesize compounds that have exceptional properties of nutraceutical, pharmacological, and biomedical interest. Pigments, fatty acids, phenols, and polysaccharides are among the main compounds investigated so far. Polysaccharides are the most exploited compounds, widely used in pharmaceutical, food, and chemical industries, which are at present entering into more advanced applications by gaining importance, from a therapeutic point of view, as antioxidant, antimicrobial, antitumor, and immunomodulatory agents. Establishing algae as an alternative supplement would complement the sustainable and environmental requirements in the framework of human health and well-being. This review focuses on the proprieties and uses of the main micro- and macroalgae metabolites, describing their potential for application in the different industrial sectors, from food/feed to chemical and pharmacological. Further, current technologies involved in bioactive molecule extraction strategies are documented.
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23

Yap, Stephanie Hui Kit, Kok Ken Chan, Swee Chuan Tjin, and Ken-Tye Yong. "Carbon Allotrope-Based Optical Fibers for Environmental and Biological Sensing: A Review." Sensors 20, no. 7 (April 5, 2020): 2046. http://dx.doi.org/10.3390/s20072046.

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Recently, carbon allotropes have received tremendous research interest and paved a new avenue for optical fiber sensing technology. Carbon allotropes exhibit unique sensing properties such as large surface to volume ratios, biocompatibility, and they can serve as molecule enrichers. Meanwhile, optical fibers possess a high degree of surface modification versatility that enables the incorporation of carbon allotropes as the functional coating for a wide range of detection tasks. Moreover, the combination of carbon allotropes and optical fibers also yields high sensitivity and specificity to monitor target molecules in the vicinity of the nanocoating surface. In this review, the development of carbon allotropes-based optical fiber sensors is studied. The first section provides an overview of four different types of carbon allotropes, including carbon nanotubes, carbon dots, graphene, and nanodiamonds. The second section discusses the synthesis approaches used to prepare these carbon allotropes, followed by some deposition techniques to functionalize the surface of the optical fiber, and the associated sensing mechanisms. Numerous applications that have benefitted from carbon allotrope-based optical fiber sensors such as temperature, strain, volatile organic compounds and biosensing applications are reviewed and summarized. Finally, a concluding section highlighting the technological deficiencies, challenges, and suggestions to overcome them is presented.
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24

Ponyaev, Alexander I., and Jana S. Glukhova. "MOLECULAR ENGINEERING OF MECHANOFLUOROCHROME LUMINESCENT PROBES." Bulletin of the Saint Petersburg State Institute of Technology (Technical University) 59 (2021): 79–85. http://dx.doi.org/10.36807/1998-9849-2021-59-85-79-85.

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Luminescent materials – developed using appropriate molecular engineering – are capable of signaling about various irritants with high sensitivity. In particular, mechanofluorochrome materials show fluorescence emission that is sensitive to mechanical stimulation (pressure, shear, cracking, grinding). Mechanically sensitive compounds are attracting increasing interest and various molecules are synthesized that respond to mechanical stress by changing their fluorescent characteristics (emission wavelength, intensity, polarization, Stokes shift). For a deeper understanding of the relationship between the structure of the dye and its mechanofluorochrome properties, a review of compounds possessing this property is given in the work.
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Negrel, Lise, Raymonde Baltenweck, Gerard Demangeat, Françoise Le Bohec-Dorner, Camille Rustenholz, Amandine Velt, Claude Gertz, et al. "Comparative Metabolomic Analysis of Four Fabaceae and Relationship to In Vitro Nematicidal Activity against Xiphinema index." Molecules 27, no. 10 (May 10, 2022): 3052. http://dx.doi.org/10.3390/molecules27103052.

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The grapevine fanleaf virus (GFLV), responsible for fanleaf degeneration, is spread in vineyards by the soil nematode Xiphinema index. Nematicide molecules were used to limit the spread of the disease until they were banned due to negative environmental impacts. Therefore, there is a growing interest in alternative methods, including plant-derived products with antagonistic effects to X. index. In this work, we evaluated the nematicidal potential of the aerial parts and roots of four Fabaceae: sainfoin (Onobrychis viciifolia), birdsfoot trefoil (Lotus corniculatus), sweet clover (Melilotus albus), and red clover (Trifolium pratense), as well as that of sainfoin-based commercial pellets. For all tested plants, either aerial or root parts, or both of them, exhibited a nematicidal effect on X. index in vitro, pellets being as effective as freshly harvested plants. Comparative metabolomic analyses did not reveal molecules or molecule families specifically associated with antagonistic properties toward X. index, suggesting that the nematicidal effect is the result of a combination of different molecules rather than associated with a single compound. Finally, scanning electron microscope observations did not reveal the visible impact of O. viciifolia extract on X. index cuticle, suggesting that alteration of the cuticle may not be the primary cause of their nematicidal effect.
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Cadamuro, Rafael Dorighello, Isabela Maria Agustini da Silveira Bastos, Izabella Thais Silva, Ariadne Cristiane Cabral da Cruz, Diogo Robl, Louis Pergaud Sandjo, Sergio Alves, et al. "Bioactive Compounds from Mangrove Endophytic Fungus and Their Uses for Microorganism Control." Journal of Fungi 7, no. 6 (June 7, 2021): 455. http://dx.doi.org/10.3390/jof7060455.

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Mangroves are ecosystems with unique characteristics due to the high salinity and amount of organic matter that house a rich biodiversity. Fungi have aroused much interest as they are an important natural source for the discovery of new bioactive compounds, with potential biotechnological and pharmacological interest. This review aims to highlight endophytic fungi isolated from mangrove plant species and the isolated bioactive compounds and their bioactivity against protozoa, bacteria and pathogenic viruses. Knowledge about this type of ecosystem is of great relevance for its preservation and as a source of new molecules for the control of pathogens that may be of importance for human, animal and environmental health.
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PALEU, DIANA, and ILEANA-DENISA NISTOR. "Aspects regarding the preparation methods of anionic clays." Journal of Engineering Sciences and Innovation 6, no. 3 (September 17, 2021): 307–22. http://dx.doi.org/10.56958/jesi.2021.6.3.8.

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Anionic clays, layered double hydroxides, are natural or synthetic materials that have special properties, especially regarding their retention capacity. This quality is due to their lamellar structure, formed by parallel planes, different molecules of interest could be intercalated between them. This allows the use of anionic clays in various fields such as: chemical industry, food industry, pharmaceutical and medical industry, as well as environmental protection. The paper presents important aspects regarding their preparation possibilities.
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Kechida, Melek. "Update on Autoimmune Diseases Pathogenesis." Current Pharmaceutical Design 25, no. 27 (October 9, 2019): 2947–52. http://dx.doi.org/10.2174/1381612825666190709205421.

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Background: Autoimmune diseases result from the interplay of cellular effectors like T and B cells, regulatory cells in addition to molecular factors like cytokines and regulatory molecules. Methods: Different electronic databases were searched in a non-systematic way to find out the literature of interest. Results: Pathogenesis of autoimmune diseases involves typical factors such as genetic background including HLA and non HLA system genes, environmental factors such as infectious agents and inflammatory cells mainly T and B lymphocytes abnormally activated leading to immune dysfunction. Other recently reported less typical factors such as micro-RNAs, circular RNAs, myeloperoxidase, vimentine and microbiome dysbiosis seem to be potential target therapies. Conclusion: We aimed in this manuscript to review common factors in the pathogenesis of autoimmune diseases.
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Prante, Marc, Ester Segal, Thomas Scheper, Janina Bahnemann, and Johanna Walter. "Aptasensors for Point-of-Care Detection of Small Molecules." Biosensors 10, no. 9 (August 26, 2020): 108. http://dx.doi.org/10.3390/bios10090108.

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Aptamers, a group of nucleic acids which can specifically bind to a target molecule, have drawn extensive interest over the past few decades. For analytics, aptamers represent a viable alternative to gold-standard antibodies due to their oligonucleic nature combined with advantageous properties, including higher stability in harsh environments and longer shelf-life. Indeed, over the last decade, aptamers have been used in numerous bioanalytical assays and in various point-of-care testing (POCT) platforms. The latter allows for rapid on-site testing and can be performed outside a laboratory by unskilled labor. Aptamer technology for POCT is not limited just to medical diagnostics; it can be used for a range of applications, including environmental monitoring and quality control. In this review, we critically examine the use of aptamers in POCT with an emphasis on their advantages and limitations. We also examine the recent success of aptasensor technology and how these findings pave the way for the analysis of small molecules in POCT and other health-related applications. Finally, the current major limitations of aptamers are discussed, and possible approaches for overcoming these challenges are presented.
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Li, Dongxiao, Cheng Xu, Junsheng Xie, and Chengkuo Lee. "Research Progress in Surface-Enhanced Infrared Absorption Spectroscopy: From Performance Optimization, Sensing Applications, to System Integration." Nanomaterials 13, no. 16 (August 19, 2023): 2377. http://dx.doi.org/10.3390/nano13162377.

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Infrared absorption spectroscopy is an effective tool for the detection and identification of molecules. However, its application is limited by the low infrared absorption cross-section of the molecule, resulting in low sensitivity and a poor signal-to-noise ratio. Surface-Enhanced Infrared Absorption (SEIRA) spectroscopy is a breakthrough technique that exploits the field-enhancing properties of periodic nanostructures to amplify the vibrational signals of trace molecules. The fascinating properties of SEIRA technology have aroused great interest, driving diverse sensing applications. In this review, we first discuss three ways for SEIRA performance optimization, including material selection, sensitivity enhancement, and bandwidth improvement. Subsequently, we discuss the potential applications of SEIRA technology in fields such as biomedicine and environmental monitoring. In recent years, we have ushered in a new era characterized by the Internet of Things, sensor networks, and wearable devices. These new demands spurred the pursuit of miniaturized and consolidated infrared spectroscopy systems and chips. In addition, the rise of machine learning has injected new vitality into SEIRA, bringing smart device design and data analysis to the foreground. The final section of this review explores the anticipated trajectory that SEIRA technology might take, highlighting future trends and possibilities.
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Kamel, Samir, and Tawfik A. Khattab. "Recent Advances in Cellulose-Based Biosensors for Medical Diagnosis." Biosensors 10, no. 6 (June 17, 2020): 67. http://dx.doi.org/10.3390/bios10060067.

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Cellulose has attracted much interest, particularly in medical applications such as advanced biosensing devices. Cellulose could provide biosensors with enhanced biocompatibility, biodegradability and non-toxicity, which could be useful for biosensors. Thus, they play a significant role in environmental monitoring, medical diagnostic tools, forensic science, and foodstuff processing safety applications. This review summarizes the recent developments in cellulose-based biosensors targeting the molecular design principles toward medical detection purposes. The recognition/detection mechanisms of cellulose-based biosensors demonstrate two major classes of measurable signal generation, including optical and electrochemical cellulosic biosensors. As a result of their simplicity, high sensitivity, and low cost, cellulose-based optical biosensors are particularly of great interest for including label-free and label-driven (fluorescent and colorimetric) biosensors. There have been numerous types of cellulose substrates employed in biosensors, including several cellulose derivatives, nano-cellulose, bacterial cellulose, paper, gauzes, and hydrogels. These kinds of cellulose-based biosensors were discussed according to their preparation procedures and detection principle. Cellulose and its derivatives with their distinctive chemical structure have demonstrated to be versatile materials, affording a high-quality platform for accomplishing the immobilization process of biologically active molecules into biosensors. Cellulose-based biosensors exhibit a variety of desirable characteristics, such as sensitivity, accuracy, convenience, quick response, and low-cost. For instance, cellulose paper-based biosensors are characterized as being low-cost and easy to operate, while nano-cellulose biosensors are characterized as having a good dispersion, high absorbance capacity, and large surface area. Cellulose and its derivatives have been promising materials in biosensors which could be employed to monitor various bio-molecules, such as urea, glucose, cell, amino acid, protein, lactate, hydroquinone, gene, and cholesterol. The future interest will focus on the design and construction of multifunctional, miniaturized, low-cost, environmentally friendly, and integrated biosensors. Thus, the production of cellulose-based biosensors is very important.
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Suwal, Shyam, and Alice Marciniak. "Technologies for the Extraction, Separation and Purification of polyphenols – A Review." Nepal Journal of Biotechnology 6, no. 1 (January 15, 2019): 74–91. http://dx.doi.org/10.3126/njb.v6i1.22341.

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Polyphenols are high molecular weight, organic molecules mainly found in plant kingdom. They are mostly known for their positive impact on health, specifically for their antioxidant activity. Indeed, they are widely studied for the prevention of multiple diseases such as cancer, inflammatory, cardiovascular and neurodegenerative diseases. Nevertheless, extractions of these growing interest molecules remain challenging using conventional methods such as solvent extraction. That is why recent researches have focused on improving the extraction of polyphenol by using different technologies such as ultrasound, microwave, pressurized liquid, pulsed electric field, supercritical fluid and high hydrostatic pressure. In the current context, the assisted-extraction should demonstrate their potential to improve the extraction efficiency while being cost-effective and with a low environmental impact. To this end, technologies ought to, for instance, increase the solubility of polyphenol and the permeability of the cell wall. Consequently, this review is focused on the use and potential of these technologies to improve polyphenol extractions from plants as well as their purification using various methods. It discusses of the advantages and disadvantages with some examples of all these technologies assisted-extraction in comparison with conventional extraction method as well as purification technology.
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Pinheiro, Luan Ramalho, Giovanna Diniz Della Croce, Francielle Dutra Aguiar, Bruna de Oliveira Thomasi, Thaís Mirelli Rêgo Bezerra, Grasiele de Sousa Vieira Tavares, Eduardo Antônio Ferraz Coelho, Geraldo Célio Brandão, and Guilherme Rocha Pereira. "Synthesis of novel aminoquinolines with potential leishmanicidal and antimalarial biological activity / Síntese de novas aminoquinolinas com potencial actividade biológica leishmanicida e antimalárica." Brazilian Journal of Development 7, no. 12 (December 29, 2021): 118095–105. http://dx.doi.org/10.34117/bjdv7n12-527.

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Leishmaniasis is a disease transmitted by different parasite species of the genus Leishmania, while malaria, by protozoa of the genus Plasmodium sp. These diseases affect tropical and subtropical regions, where about half of the world's population live. However, leishmaniasis and malaria are considered neglected diseases because these regions are poor, and consequently have precarious essential sanitation networks. In response to the lack of vaccines and effective medical measures, some natural and synthetic medicines are used as forms of treatment, such as quinoline derivatives necessary to treat malaria. Even so, the parasites have shown resistance to forms of treatment, which makes needed the constant development of new drugs with potential against them. Quinoline derivatives, chloroquine analogues, have potential activity for the diseases of interest, while anilines are molecules used in nucleophilic reactions on different substrates. Therefore, the work consisted of exploring the synthesis between these two compounds through subsequent reactions involving the formation of intermediates that resulted in the products of interest. Twelve novel derivatives with potential leishmanicidal and antimalarial biological activity were synthesized. The molecules produced were purified and rightly characterized by several methods, such as mass spectrometry, infrared spectroscopy, and Nuclear Magnetic Resonance of Carbon (13C) and Hydrogen (1H). Also, were obtained the melting points of the synthesized molecules. Finally, all products were sent for biological tests against the parasites, getting highly effective results for the protozoa responsible for leishmaniasis.
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Law, Cheryl Suwen, Siew Yee Lim, Andrew D. Abell, Nicolas H. Voelcker, and Abel Santos. "Nanoporous Anodic Alumina Photonic Crystals for Optical Chemo- and Biosensing: Fundamentals, Advances, and Perspectives." Nanomaterials 8, no. 10 (October 4, 2018): 788. http://dx.doi.org/10.3390/nano8100788.

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Optical sensors are a class of devices that enable the identification and/or quantification of analyte molecules across multiple fields and disciplines such as environmental protection, medical diagnosis, security, food technology, biotechnology, and animal welfare. Nanoporous photonic crystal (PC) structures provide excellent platforms to develop such systems for a plethora of applications since these engineered materials enable precise and versatile control of light–matter interactions at the nanoscale. Nanoporous PCs provide both high sensitivity to monitor in real-time molecular binding events and a nanoporous matrix for selective immobilization of molecules of interest over increased surface areas. Nanoporous anodic alumina (NAA), a nanomaterial long envisaged as a PC, is an outstanding platform material to develop optical sensing systems in combination with multiple photonic technologies. Nanoporous anodic alumina photonic crystals (NAA-PCs) provide a versatile nanoporous structure that can be engineered in a multidimensional fashion to create unique PC sensing platforms such as Fabry–Pérot interferometers, distributed Bragg reflectors, gradient-index filters, optical microcavities, and others. The effective medium of NAA-PCs undergoes changes upon interactions with analyte molecules. These changes modify the NAA-PCs’ spectral fingerprints, which can be readily quantified to develop different sensing systems. This review introduces the fundamental development of NAA-PCs, compiling the most significant advances in the use of these optical materials for chemo- and biosensing applications, with a final prospective outlook about this exciting and dynamic field.
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Monkenbusch, Michael. "Polymers: When S(Q,t) is not what you think! The role of dynamic RPA." EPJ Web of Conferences 272 (2022): 01006. http://dx.doi.org/10.1051/epjconf/202227201006.

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Investigating a (polymeric) soft-matter system with several components often is aimed at the observation of the motions/mobilities of one of the components. The normal approach to this request in the context of quasielastic neutron scattering (e.g. NSE) is to put contrast on the targeted component, typically by leaving it hydrogenated and have the rest (surrounding, matrix) deuterated. In simple systems with only one molecular species as a homo-polymer melt with a few of the molecules contrasted (e.g. 10% h in 90% d) -provided the h-and d-molecular varieties behave sufficiently equalthis strategy yields a valid single chain (molecule) structure factor S(Q,t)/S(Q), even for a 50/50% mixture. However, if the component of interest and the matrix are of different kind, unexpected distortions of the observed S(Q,t) may occur. Interpretation of such results in terms of the single chain structure factor would then lead to erroneous conclusions. In this contribution the conditions, under which these distortions will occur, are discussed and how dynamic RPA may help to cope with them is explained. A practical method to apply this correction to polymer and similar problems is presented and an experimental verification is discussed [1, 12].
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36

Bohlin, Lars, Ulf Göransson, and Anders Backlund. "Modern pharmacognosy: Connecting biology and chemistry." Pure and Applied Chemistry 79, no. 4 (January 1, 2007): 763–74. http://dx.doi.org/10.1351/pac200779040763.

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In many countries today, the number of students selecting chemistry for higher studies is decreasing. At the same time, interest in the environmental aspects of chemistry, green chemistry, and sustainable use of natural products is increasing among the young generation of students. By modernizing and renewing a venerable proven science, pharmacognosy would have a strategic position to connect biology and chemistry. This multidisciplinary subject is important for discovery of novel and unique molecules with drug potential, and for revealing unknown targets, by studying evolutionary structure-activity optimization in nature. In this paper, the overall aim and strategies of our research are presented and exemplified by three different research projects.Natural products are involved in scientific issues important for a sustainable society, and a multidisciplinary subject such as pharmacognosy can, therefore, be useful in increasing future interest in both chemistry and biology.
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37

Liu, Qiang, and Li-Zhu Wu. "Recent advances in visible-light-driven organic reactions." National Science Review 4, no. 3 (April 8, 2017): 359–80. http://dx.doi.org/10.1093/nsr/nwx039.

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Abstract In recent years, visible-light-driven organic reactions have been experiencing a significant renaissance in response to topical interest in environmentally friendly green chemical synthesis. The transformations using inexpensive, readily available visible-light sources have come to the forefront in organic chemistry as a powerful strategy for the activation of small molecules. In this review, we focus on recent advances in the development of visible-light-driven organic reactions, including aerobic oxidation, hydrogen-evolution reactions, energy-transfer reactions and asymmetric reactions. These key research topics represent a promising strategy towards the development of practical, scalable industrial processes with great environmental benefits.
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38

Corral, Paulina, Mohammad A. Amoozegar, and Antonio Ventosa. "Halophiles and Their Biomolecules: Recent Advances and Future Applications in Biomedicine." Marine Drugs 18, no. 1 (December 30, 2019): 33. http://dx.doi.org/10.3390/md18010033.

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The organisms thriving under extreme conditions better than any other organism living on Earth, fascinate by their hostile growing parameters, physiological features, and their production of valuable bioactive metabolites. This is the case of microorganisms (bacteria, archaea, and fungi) that grow optimally at high salinities and are able to produce biomolecules of pharmaceutical interest for therapeutic applications. As along as the microbiota is being approached by massive sequencing, novel insights are revealing the environmental conditions on which the compounds are produced in the microbial community without more stress than sharing the same substratum with their peers, the salt. In this review are reported the molecules described and produced by halophilic microorganisms with a spectrum of action in vitro: antimicrobial and anticancer. The action mechanisms of these molecules, the urgent need to introduce alternative lead compounds and the current aspects on the exploitation and its limitations are discussed.
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39

Yoo, Choong-Shik. "Barochemistry to Multifunctional High Energy Density Solid: Extended Phases of N2, CO, and N2+CO at High Pressures." MRS Advances 2, no. 48 (2017): 2581–86. http://dx.doi.org/10.1557/adv.2017.382.

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ABSTRACTMany simple diatomic and triatomic molecules such as N2 and CO2 have the potential to form extended “polymeric” solids under extreme conditions, which can store a large sum of chemical energy in its three-dimensional network structures made of strong covalent bonds. Diatomic nitrogen is particularly of interest because of the uniquely large energy difference between that of the single bond (160 kJ/mol) and that of the triple bond (954 kJ/mol). As such, the transformation of a singly bonded polymeric nitrogen back to triply-bonded diatomic nitrogen molecules can release nearly 5 times the energy of TNT without any negative environmental impact. In this paper, we will describe our recent research efforts to synthesize novel extended phases of isoelectronic systems of N2 and CO, as well as those of N2+CO mixtures to lower the transition pressures and enhance the stability of recovered products at ambient condition.
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40

Bjerk, Thiago R., Patricia Severino, Sona Jain, Conrado Marques, Amélia M. Silva, Tatiana Pashirova, and Eliana B. Souto. "Biosurfactants: Properties and Applications in Drug Delivery, Biotechnology and Ecotoxicology." Bioengineering 8, no. 8 (August 13, 2021): 115. http://dx.doi.org/10.3390/bioengineering8080115.

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Surfactants are amphiphilic compounds having hydrophilic and hydrophobic moieties in their structure. They can be of synthetic or of microbial origin, obtained respectively from chemical synthesis or from microorganisms’ activity. A new generation of ecofriendly surfactant molecules or biobased surfactants is increasingly growing, attributed to their versatility of applications. Surfactants can be used as drug delivery systems for a range of molecules given their capacity to create micelles which can promote the encapsulation of bioactives of pharmaceutical interest; besides, these assemblies can also show antimicrobial properties. The advantages of biosurfactants include their high biodegradability profile, low risk of toxicity, production from renewable sources, functionality under extreme pH and temperature conditions, and long-term physicochemical stability. The application potential of these types of polymers is related to their properties enabling them to be processed by emulsification, separation, solubilization, surface (interfacial) tension, and adsorption for the production of a range of drug delivery systems. Biosurfactants have been employed as a drug delivery system to improve the bioavailability of a good number of drugs that exhibit low aqueous solubility. The great potential of these molecules is related to their auto assembly and emulsification capacity. Biosurfactants produced from bacteria are of particular interest due to their antibacterial, antifungal, and antiviral properties with therapeutic and biomedical potential. In this review, we discuss recent advances and perspectives of biosurfactants with antimicrobial properties and how they can be used as structures to develop semisolid hydrogels for drug delivery, in environmental bioremediation, in biotechnology for the reduction of production costs and also their ecotoxicological impact as pesticide alternative.
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Hirose, Jun. "Diversity and Evolution of Integrative and Conjugative Elements Involved in Bacterial Aromatic Compound Degradation and Their Utility in Environmental Remediation." Microorganisms 11, no. 2 (February 9, 2023): 438. http://dx.doi.org/10.3390/microorganisms11020438.

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Integrative and conjugative elements (ICEs) are mobile DNA molecules that can be transferred through excision, conjugation, and integration into chromosomes. They contribute to the horizontal transfer of genomic islands across bacterial species. ICEs carrying genes encoding aromatic compound degradation pathways are of interest because of their contribution to environmental remediation. Recent advances in DNA sequencing technology have increased the number of newly discovered ICEs in bacterial genomes and have enabled comparative analysis of their evolution. The two different families of ICEs carry various aromatic compound degradation pathway genes. ICEclc and its related ICEs contain a number of members with diverse catabolic capabilities. In addition, the Tn4371 family, which includes ICEs that carry the chlorinated biphenyl catabolic pathway, has been identified. It is apparent that they underwent evolution through the acquisition, deletion, or exchange of modules to adapt to an environmental niche. ICEs have the property of both stability and mobility in the chromosome. Perspectives on the use of ICEs in environmental remediation are also discussed.
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42

Idris, Azeez O., Ekemena O. Oseghe, Titus A. M. Msagati, Alex T. Kuvarega, Usisipho Feleni, and Bhekie Mamba. "Graphitic Carbon Nitride: A Highly Electroactive Nanomaterial for Environmental and Clinical Sensing." Sensors 20, no. 20 (October 10, 2020): 5743. http://dx.doi.org/10.3390/s20205743.

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Graphitic carbon nitride (g-C3N4) is a two-dimensional conjugated polymer that has attracted the interest of researchers and industrial communities owing to its outstanding analytical merits such as low-cost synthesis, high stability, unique electronic properties, catalytic ability, high quantum yield, nontoxicity, metal-free, low bandgap energy, and electron-rich properties. Notably, graphitic carbon nitride (g-C3N4) is the most stable allotrope of carbon nitrides. It has been explored in various analytical fields due to its excellent biocompatibility properties, including ease of surface functionalization and hydrogen-bonding. Graphitic carbon nitride (g-C3N4) acts as a nanomediator and serves as an immobilization layer to detect various biomolecules. Numerous reports have been presented in the literature on applying graphitic carbon nitride (g-C3N4) for the construction of electrochemical sensors and biosensors. Different electrochemical techniques such as cyclic voltammetry, electrochemiluminescence, electrochemical impedance spectroscopy, square wave anodic stripping voltammetry, and amperometry techniques have been extensively used for the detection of biologic molecules and heavy metals, with high sensitivity and good selectivity. For this reason, the leading drive of this review is to stress the importance of employing graphitic carbon nitride (g-C3N4) for the fabrication of electrochemical sensors and biosensors.
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43

Brighenti, Roberto, and Mattia Pancrazio Cosma. "Smart actuation of liquid crystal elastomer elements: cross-link density-controlled response." Smart Materials and Structures 31, no. 1 (November 22, 2021): 015012. http://dx.doi.org/10.1088/1361-665x/ac34bf.

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Abstract Liquid crystal elastomers (LCEs) exhibit some remarkable physical properties, such as the reversible large mechanical deformation induced by proper environmental stimuli of different nature, such as the thermal stimulus, allowing their use as soft actuators. The unique features displayed by LCE are originated from their anisotropic microstructure characterized by the preferential orientation of the mesogen molecules embedded in the polymer network. An open issue in the design of LCEs is how to control their actuation effectiveness: the amount of mesogens molecules, how they are linked to the network, the nematic order degree, the cross-link density are some controllable parameters whose spatial distribution, in general, cannot be tuned except for the last one. In this paper, we develop a theoretical micromechanical-based framework to model and explore the effect of the network cross-link density on the mechanical actuation of LCE elements. In this context, the light-induced polymerization (photopolymerization) for obtaining the elastomers’ cross-linked network is of particular interest, being suitable for precisely tuning the cross-link density distribution within the material. This technology enables to obtain a molecular-scale architected LCEs, allowing the optimal design of the obtainable actuation. The possibility to properly set the cross-link density arrangement within the smart structural element (LCE microstructure design and optimization), represents an intriguing way to create molecular-scale engineered LCE elements having a material microstructure encoding the desired actuation capabilities.
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Niedbała, Patryk, Kajetan Dąbrowa, Sylwia Wasiłek, and Janusz Jurczak. "Recognition of Chiral Carboxylates by Synthetic Receptors." Molecules 26, no. 21 (October 24, 2021): 6417. http://dx.doi.org/10.3390/molecules26216417.

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Recognition of anionic species plays a fundamental role in many essential chemical, biological, and environmental processes. Numerous monographs and review papers on molecular recognition of anions by synthetic receptors reflect the continuing and growing interest in this area of supramolecular chemistry. However, despite the enormous progress made over the last 20 years in the design of these molecules, the design of receptors for chiral anions is much less developed. Chiral recognition is one of the most subtle types of selectivity, and it requires very precise spatial organization of the receptor framework. At the same time, this phenomenon commonly occurs in many processes present in nature, often being their fundamental step. For these reasons, research directed toward understanding the chiral anion recognition phenomenon may lead to the identification of structural patterns that enable increasingly efficient receptor design. In this review, we present the recent progress made in the area of synthetic receptors for biologically relevant chiral carboxylates.
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Hasan, Anwarul, Md Nurunnabi, Mahboob Morshed, Arghya Paul, Alessandro Polini, Tapas Kuila, Moustafa Al Hariri, Yong-kyu Lee, and Ayad A. Jaffa. "Recent Advances in Application of Biosensors in Tissue Engineering." BioMed Research International 2014 (2014): 1–18. http://dx.doi.org/10.1155/2014/307519.

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Biosensors research is a fast growing field in which tens of thousands of papers have been published over the years, and the industry is now worth billions of dollars. The biosensor products have found their applications in numerous industries including food and beverages, agricultural, environmental, medical diagnostics, and pharmaceutical industries and many more. Even though numerous biosensors have been developed for detection of proteins, peptides, enzymes, and numerous other biomolecules for diverse applications, their applications in tissue engineering have remained limited. In recent years, there has been a growing interest in application of novel biosensors in cell culture and tissue engineering, for example, real-time detection of small molecules such as glucose, lactose, and H2O2as well as serum proteins of large molecular size, such as albumin and alpha-fetoprotein, and inflammatory cytokines, such as IFN-g and TNF-α. In this review, we provide an overview of the recent advancements in biosensors for tissue engineering applications.
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46

Lucas, Anne D., Shirley J. Gee, Bruce D. Hammock, and James N. Seiber. "Integration of Immunochemical Methods with Other Analytical Techniques for Pesticide Residue Determination." Journal of AOAC INTERNATIONAL 78, no. 3 (May 1, 1995): 585–91. http://dx.doi.org/10.1093/jaoac/78.3.585.

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Abstract The growing volume of literature concerning immunoassay analysis for trace levels of agrochemicals and other low molecular weight contaminants in various matrixes is indicative of the tremendous interest in and utility of this analytical technique. Most immunoassay methods described in the literature analyze compounds directly, for example, a herbicide in water, or involve solvent exchange of an organic sample extract or dilution of an aqueous-based sample to minimize the matrix effect. As immunoassay for small molecules becomes widely accepted and applied, new challenges involving more complex chemicals in more difficult matrixes arise. The integration of “classical” analytical chemistry with immunochemistry can provide new techniques and approaches useful in discovering the movement, mode of action, and ultimate impact of certain chemicals on humans and the environment.
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Aldosari, Haia. "Review of Carbon Nanotube Toxicity and Evaluation of Possible Implications to Occupational and Environmental Health." Nano Hybrids and Composites 40 (July 31, 2023): 35–49. http://dx.doi.org/10.4028/p-4gnl3o.

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Carbon nanotubes (CNTs) are nanostructures made from rolled graphene planes and have several intriguing chemical and physical characteristics. Allotropes of carbon having a nanostructure that can have a length-to-diameter ratio greater than 1,000,000 are known as carbon nanotubes (CNTs). These cylindrical carbon molecules have unique features that could make them valuable in a variety of nanotechnology applications. Their distinct surface area, stiffness, strength, and durability have generated a significant amount of interest in the health industry to achieve bio-functionalities, CNTs can be connected with a variety of biological substances, such as hormones, proteins, and nucleic acids. There are two types of CNTs: single-walled (SWNTs) and multi-walled (MWNTs). Their high aspect ratio, ultralightweight, strength, strong thermal conductivity, and electrical properties ranging from metallic to semiconducting are just a few of their intriguing characteristics. Drug delivery, blood cancer, breast cancer, brain cancer, liver cancer, cervical cancer, immunological treatment, biomedical imaging, biosensors, and tissue engineering are all areas where CNTs are beneficial, and the toxicology of carbon nanotubes is also discussed here.
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Dias, João A., Pedro Machado, and José Ribeiro. "From Atmospheric Evolution to the Search of Species of Astrobiological Interest in the Solar System—Case Studies Using the Planetary Spectrum Generator." Atmosphere 13, no. 3 (March 12, 2022): 461. http://dx.doi.org/10.3390/atmos13030461.

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The study of minor chemical species in terrestrial planets’ atmospheres can teach us about the chemistry, dynamics and evolution of the atmospheres through time. Phosphine or methane on terrestrial planets are potential biosignatures, such that their detection may signify the presence of life on a planet. Therefore, the search for these species in the solar system is an important step for the subsequent application of the same techniques to exoplanetary atmospheres. To study atmospheric depletion and the evolution of water abundance in the atmospheres of terrestrial planets, the estimation of the D/H ratio and its spatial and temporal variability is used. We used the Planetary Spectrum Generator (PSG), a radiative transfer suite, with the goal of simulating spectra from observations of Venus, Mars and Jupiter, searching for minor chemical species. The present study contributes to highlight that the PSG is an efficient tool for studying minor chemical species and compounds of astrobiological interest in planetary atmospheres, allowing to perform the detection and retrieval of the relevant molecular species. Regarding detection, it is effective in disentangling different molecular opacities affecting observations. In order to contribute to the scientific community that is focused on the study of minor chemical species in the solar system’s atmospheres, using this tool, in this work, we present the results from an analysis of observations of Venus, Mars and Jupiter, by comparison of observations with simulations in the infrared (IR). The first step was to clearly identify the position of molecular features using our model simulations, since the molecular absorption/emission features of different molecules tend to overlap. For this step, we used the method of the variation of abundances. The second step was to determine the molecular abundances and compare them with values from the literature using the retrieval method and the line depth ratio method. For Venus, our study of SO2-related observations by the Texas Echelon Cross Echelle Spectrograph (TEXES) at 7.4 μm enabled the identification of absorption lines due to sulphur dioxide and carbon dioxide as well as constrain the abundance of SO2 at the cloud top. Phosphine was not detected in the comparison between the simulation and TEXES IR observations around 10.5 μm. For Mars, both a positive and a non-detection of methane were studied using PSG simulations. The related spectra observations in the IR, at approximately 3.3 μm, correspond, respectively, to the Mars Express (MEx) and ExoMars space probes. Moreover, an estimate of the deuterium-to-hydrogen ratio (D/H ratio) was obtained by comparing the simulations with observations by the Echelon Cross Echelle Spectrograph (EXES) onboard the Stratospheric Observatory for Infrared Astronomy (SOFIA) at approximately 7.19–7.23 μm. For Jupiter, the detection of ammonia, phosphine, deuterated methane and methane was studied, by comparing the simulations with IR observations by the Infrared Space Observatory (ISO) at approximately 7–12 μm. Moreover, the retrieval of the profiles of ammonia and phosphine was performed.
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49

Filipczak, Nina, Satya Siva Kishan Yalamarty, Xiang Li, Farzana Parveen, and Vladimir Torchilin. "Developments in Treatment Methodologies Using Dendrimers for Infectious Diseases." Molecules 26, no. 11 (May 31, 2021): 3304. http://dx.doi.org/10.3390/molecules26113304.

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Dendrimers comprise a specific group of macromolecules, which combine structural properties of both single molecules and long expanded polymers. The three-dimensional form of dendrimers and the extensive possibilities for use of additional substrates for their construction creates a multivalent potential and a wide possibility for medical, diagnostic and environmental purposes. Depending on their composition and structure, dendrimers have been of interest in many fields of science, ranging from chemistry, biotechnology to biochemical applications. These compounds have found wide application from the production of catalysts for their use as antibacterial, antifungal and antiviral agents. Of particular interest are peptide dendrimers as a medium for transport of therapeutic substances: synthetic vaccines against parasites, bacteria and viruses, contrast agents used in MRI, antibodies and genetic material. This review focuses on the description of the current classes of dendrimers, the methodology for their synthesis and briefly drawbacks of their properties and their use as potential therapies against infectious diseases.
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50

Al-Manhel, Alaa J. A. "Application of Microbial Enzymes in Dairy Products: A Review." Basrah Journal of Agricultural Sciences 31, no. 1 (April 15, 2018): 20–30. http://dx.doi.org/10.37077/25200860.2018.72.

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Enzymes produced by microbial sources are biological molecules that known to catalysts biochemical reactions which roles involve in lead to stimulate the necessary chemical reactions, as well as to the formation of fermented products. Microbial protease, lipase and ?-galactosidase are important examples of such interest in industrial food and dairy product. This is due to their thermoresistant, thermostability and thermoacidophilic properties. In brief, hydrolyses are the substrate which includes some enzymatic reaction that allows to avoid the health and environmental problems, and also to catalyses chemical reaction during the formation of flavor compounds or prebiotic and other products additives in the production and development of healthy dairy food products. Thus, enzymes are one of the relatively important factor that expected to be utilized in large-scale in the process of products development. This review focused on the importance and application of three major enzymes that microbial produce which are of great interest in dairy industries and have positive impact on consumer’s health.
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