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1.
Molecules ; 28(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37241924

RESUMO

The solubilization capacity of a series of sustainable phenylalanine-derived surface-active ionic liquids (SAILs) was evaluated towards polycyclic aromatic hydrocarbons-naphthalene, anthracene and pyrene. The key physico-chemical parameters of the studied systems (critical micelle concentration, spectral properties, solubilization parameters) were determined, analyzed and compared with conventional cationic surfactant, CTABr. For all studied PAH solubilization capacity increases with extension of alkyl chain length of PyPheOCn SAILs reaching the values comparable to CTABr for SAILs with n = 10-12. A remarkable advantage of the phenylalanine-derived SAILs PyPheOCn and PyPheNHCn is a possibility to cleave enzymatically ester and/or amide bonds under mild conditions, to separate polycyclic aromatic hydrocarbons in situ. A series of immobilized enzymes was tested to determine the most suitable candidates for tunable decomposition of SAILs. The decomposition pathway could be adjusted depending on the choice of the enzyme system, reaction conditions, and selection of SAILs type. The evaluated systems can provide selective cleavage of the ester and amide bond and help to choose the optimal decomposition method of SAILs for enzymatic recycling of SAILs transformation products or as a pretreatment towards biological mineralization. The concept of a possible practical application of studied systems for PAHs solubilization/separation was also discussed focusing on sustainability and a green chemistry approach.

2.
Nanomaterials (Basel) ; 13(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36839048

RESUMO

This paper aims to analyse the state-of-the-art of graphene-based materials and devices designed for use in space. The goal is to summarise emerging research studies, contextualise promising findings, and discuss underway strategies to address some specific space-related problems. To complete our overview of graphene-based technology and address the relevance of graphene in the wide scenario of the space economy, we also provide an analysis of worldwide patents and the scientific literature for aerospace applications in the period 2010-2021. We analysed global trends, country distributions, top assignees, and funding sponsors, evidencing a general increase for the period considered. These indicators, integrated with market information, provide a clear evaluation of the related technology trends and readiness levels.

3.
Pharm Res ; 39(10): 2379-2390, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35854078

RESUMO

The present review describes the state of the art in the conversion of pharmaceutically active ingredients (API) in amphiphilic Ionic Liquids (ILs) as alternative drug delivery systems. In particular, we focus our attention on the compounds generated by ionic exchange and without original counterions which generate different systems in comparison with the simple mixtures. In water, these new amphiphiles show similar or even better properties as surfactants in comparison with their precursors. Cations such as 1-alkyl-3-methyl-imidazolium and anions such as dioctyl sulfosuccinate or sodium dodecyl sulfate appear as the amphiphilic components most studied. In conclusion, this work shows interesting information on several promissory compounds and they appear as an interesting challenge to extend the application of ILs in the medical field.


Assuntos
Líquidos Iônicos , Ânions , Cátions , Ácido Dioctil Sulfossuccínico , Micelas , Dodecilsulfato de Sódio , Tensoativos , Água
4.
J Appl Clin Med Phys ; 22(11): 172-184, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34610206

RESUMO

PURPOSE: To develop a Natural Language Processing (NLP) and Machine Learning (ML) pipeline that can be integrated into an Incident Learning System (ILS) to assist radiation oncology incident learning by semi-automating incident classification. Our goal was to develop ML models that can generate label recommendations, arranged according to their likelihoods, for three data elements in Canadian NSIR-RT taxonomy. METHODS: Over 6000 incident reports were gathered from the Canadian national ILS as well as our local ILS database. Incident descriptions from these reports were processed using various NLP techniques. The processed data with the expert-generated labels were used to train and evaluate over 500 multi-output ML algorithms. The top three models were identified and tuned for each of three different taxonomy data elements, namely: (1) process step where the incident occurred, (2) problem type of the incident and (3) the contributing factors of the incident. The best-performing model after tuning was identified for each data element and tested on unseen data. RESULTS: The MultiOutputRegressor extended Linear SVR models performed best on the three data elements. On testing, our models ranked the most appropriate label 1.48 ± 0.03, 1.73 ± 0.05 and 2.66 ± 0.08 for process-step, problem-type and contributing factors respectively. CONCLUSIONS: We developed NLP-ML models that can perform incident classification. These models will be integrated into our ILS to generate a drop-down menu. This semi-automated feature has the potential to improve the usability, accuracy and efficiency of our radiation oncology ILS.


Assuntos
Processamento de Linguagem Natural , Radioterapia (Especialidade) , Canadá , Humanos , Aprendizado de Máquina , Gestão de Riscos
5.
Molecules ; 26(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279374

RESUMO

Most of the commonly used Ionic Liquids (ILs) contain bulky organic cations with suitable anions. With our COMPLET (Concept of Melting Point Lowering due to Ethoxylation), we follow a different approach. We use simple, low-toxic, cheap, and commercially available anions of the type Cx(EO)yCH2COO- to liquefy presumably any simple metal ion, independently of its charge. In the simplest case, the cation can be sodium or lithium, but synthesis of Ionic Liquids is also possible with cations of higher valences such as transition or rare earth metals. Anions with longer alkyl chains are surface active and form surface active ionic liquids (SAILs), which combine properties of ionic and nonionic surfactants at room temperature. They show significant structuring even in their pure state, i.e., in the absence of water or any other added solvent. This approach offers new application domains that go far beyond the common real or hypothetical use of classical Ionic Liquids. Possible applications include the separation of rare earth metals, the use as interesting media for metal catalysis, or the synthesis of completely new materials (for example, in analogy to metal organic frameworks).

6.
Ecotoxicol Environ Saf ; 186: 109784, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31634657

RESUMO

Surface-active ionic liquids (SAILs) belonging to the series of N-alkylmethylimidazolium halides [C8mimX] (X = Br, Cl, and BF4) and [CnmimBr] (n = 10, 12, 14, and 16) were employed to understand the influence of hydrophobicity of alkyl chain length and the chaotropicity of counter-ions of SAILs on the micellization, antimicrobial action and cytotoxicity properties. The micellization phenomenon of SAILs in an aqueous environment was examined employing tensiometry and steady-state fluorescence spectrophotometry. The corresponding interfacial parameters viz., critical micelle concentration (CMC), effectiveness (γCMC), surface pressure (ПCMC), maximum surface excess concentration (Гmax), and the minimum area engaged per molecule (Amin) at the air-water interface were evaluated at 303.15 K. These experimental findings were monitored and geometrically optimized theoretically using Gaussian software to highlight the recent advances in this field of theoretical calculations for putative structure. The simulation descriptors correlated the micellization behavior as a function of hydrophobicity which may contribute to obtaining awareness on their ecological behavior and fate. In addition, the biological screening of all the examined SAILs was undertaken with a combined experimental and theoretical (optimized) method against bacteria and fungus. Results revealed that SAILs with the alkyl chain-length greater than C8- act as a fair antimicrobial agent against the selected microbial strain which is attributed to the enhanced degree of SAILs hydrophobicity. The cytotoxicity of these imidazolium-based SAILs was also assessed on the cervical human cell line (HeLa) using the MTT cell viability assay and the data thus obtained were subjected to statistical analysis.


Assuntos
Líquidos Iônicos/química , Tensoativos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imidazóis/química , Líquidos Iônicos/farmacologia , Micelas , Tensoativos/farmacologia , Água/química
7.
Arch Microbiol ; 201(6): 855-862, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30929030

RESUMO

Synthetic biology, the design and synthesis of synthetic biological systems from DNA to whole cells, has provided us with the ultimate tools for space exploration and colonisation. Herein, we explore some of the most significant advances and future prospects in the field of synthetic biology, in the context of astrobiology and terraforming.


Assuntos
Exobiologia/tendências , Biologia Sintética/tendências , DNA/síntese química , DNA/genética , Exobiologia/métodos , Voo Espacial , Biologia Sintética/métodos
8.
J Colloid Interface Sci ; 446: 263-71, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25681783

RESUMO

Ester functionalized surface active ionic liquids (SAILs), [CnEMorph][Br], where n=8, 12 and 16, comprising of long hydrophobic chain appended with ester functionality connected to N-methylmorpholine group have been synthesized and investigated for their aggregation behavior and cytotoxicity. A variety of state of art techniques viz. tensiometry, conductometry, isothermal titration calorimetry (ITC), spectrofluorometry, dynamic light scattering (DLS) and atomic force microscopy (AFM) have been employed to get insight into the various aspects of aggregation behavior. The investigated SAILs have been found to possess lower critical aggregation concentration (cac) and greater adsorption efficacy at air-solution interface as compared to earlier reported non-functionalized SAILs or conventional ionic surfactants. Further, the thermal stability of these morpholinium cationics has been evaluated by thermal gravimetric analysis (TGA). These SAILs have been found to be non-cytotoxic in the concentration range generally required for different biological applications as judged by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on the C6 glioma cell line. The dependence of characteristic properties of aggregation on alkyl chain length has been established.


Assuntos
Proliferação de Células , Ésteres/química , Glioma/química , Líquidos Iônicos/química , Morfolinas/química , Água/química , Calorimetria , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Espectrometria de Fluorescência , Células Tumorais Cultivadas
9.
J Anal Psychol ; 59(1): 47-59, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24467352

RESUMO

The spatial metaphor of Utopia is considered from a Jungian perspective along with its role in Russian culture and in analysis. Such post-Jungian concepts as the cultural complex and the archetypal story pattern of a victim are used in considering the desperate longing for a rescuer in patients' narratives and in Russian society. A clinical vignette is provided to illustrate these ideas.


Assuntos
Cultura , Teoria Junguiana , Metáfora , Terapia Psicanalítica , Utopias , Humanos , Federação Russa
10.
J Colloid Interface Sci ; 412: 24-30, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24144370

RESUMO

A series of salt-free catanionic surface active ionic liquids (SAILs), 1-alkyl-3-methylimidazolim alkyl sulfates (denoted as [Cnmim][CmSO4], n=6, 8, 10; m=12 and n=4; m=10, 14) were synthesized by an ion exchange reaction and their surface properties in aqueous solution were examined systematically by surface tension, fluorescence and electrical conductivity measurements. As catanionic surfactants, these SAILs exhibit notably higher surface activity, compared to the cationic or anionic analogues. Increment in both cationic and anionic alkyl chain lengths for [Cnmim][CmSO4] can both improve the amphiphilic character remarkably. This can be ascribed to cooperative interactions as formation of catanionic pairs between alkyl-substituted imidazolium cations and alkyl sulfate anions. The negative micellization Gibbs free energy values prove that the micellization of all the 1-alkyl-3-methylimidazolim alkyl sulfates investigated is a spontaneous process. Any additional CH2 group makes the micellization process easier regardless if it is on a cation or an anion. When keeping the total carbon atom number constant, we find that the [Cnmim][CmSO4] molecules with greater asymmetric alkyl chains display superior surface activity. This work indicates that the self-assembly of these imidazolium-based salt-free catanionic SAILs can be tailored by adjusting the mismatch of alkyl chains. These SAILs are expected to have potential applications in the fields of colloidal and interface and nanomaterial synthesis.

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