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One solution to comply with the strict regulations of the European Commission and reduce the environmental footprint of composites is the use of composite materials based on bio-polymers and fillers from natural resources. The aim of our work was to obtain and analyze the properties of bio-polymer nanocomposites based on bio-PA (PA) and feather keratin-halloysite nanohybrid. Keratin (KC) was mixed with halloysite (H) as such or with the treated surface under dynamic conditions, resulting in two nanohybrids: KCHM and KCHE. The homogenization of PA with the two nanohybrids was conducted using the extrusion processing process. Two types of nanocomposites, PA-KCHM and PA-KCHE, with 5 wt.% KC and 1 wt.% H were obtained. The properties were analyzed using SEM, XRD, FTIR, RAMAN, TGA, DSC, tensile/impact tests, DMA, and nanomechanical tests. The best results were obtained for PA-KCHE due to the stronger interaction between the components and the uniform dispersion of the nanohybrid in the PA matrix. Improvements in the modulus of elasticity and of the surface hardness by approx. 75% and 30%, respectively, and the resistance to scratch were obtained. These results are promising and constitute a possible alternative to synthetic polymer composites for the automotive industry.
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Introduction: The study examines the role of chess in the development of children from the perspectives of parents. The research focused on analyzing the parents' perceptions about chess's role in their children's development, on finding out how the perception of parents differs depending on whether they know how to play chess or not, and on outlining the profile of the parents whose children play chess.The study was conducted in Romania. Methods: In order to conduct the study, a quantitative research method was used, while having as a research instrument a non-standardized questionnaire. The questionnaire was applied to parents of chess-playing children who are members of chess clubs from Romania. The sample of the study comprises 774 respondents. Results: The results of our research showed that parents are of the opinion that chess helps children develop their cognitive abilities, their character and their competitive spirit. Most of the parents focused on highlighting the positive effects of chess on the development of their children. Parents also considered that chess helped their children develop positive emotions and helped them overcome negative emotions. The results revealed differences between the opinions of parents depending on whether they know how to play chess or not. Thus, parents who do know how to play chess were more likely to focus on the positive effects of the game on the development of their children, and those who know how to play chess were also more satisfied with their children's accumulated knowledge following chess lessons. Discussion: Findings extend our understanding of how parents perceive the way chess influences the development of their children, it offered us a perspective on the perceived benefits of chess, benefits which should be further analyzed in order to identify under what circumstances chess could be introduced in the school curriculum.
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In recent years, the unprecedented rise of bacterial antibiotic resistance together with the lack of adequate therapies have made the treatment of skin infections and chronic wounds challenging, urging the scientific community to focus on the development of new and more efficient treatment strategies. In this context, there is a growing interest in the use of natural molecules with antimicrobial features, capable of supporting wound healing i.e., antimicrobial peptides (AMPs), for the treatment of skin and soft tissue infections. In this review, we give a short overview of the bacterial skin infections as well as some of the classic treatments used for topical application. We then summarize the AMPs classes, stressing the importance of the appropriate selection of the peptides based on their characteristics and physicochemical properties in order to maximize the antibacterial efficacy of the therapeutic systems against multi-drug resistant pathogens. Additionally, the present paper provides a comprehensive and rigorous assessment of the latest clinical trials investigating the efficacy of AMPs in the treatment of skin and soft tissue infections, highlighting the relevant outcomes. Seeking to obtain novel and improved compounds with synergistic activity, while also decreasing some of the known side effects of AMPs, we present two employed strategies using AMPs: (i) AMPs-conjugated nanosystems for systemic and topical drug delivery systems and (ii) antibiotics-peptide conjugates as a strategy to overcome antibiotics resistance. Finally, an important property of some of the AMPs used in wound treatment is highlighted: their ability to help in wound healing by generally promoting cell proliferation and migration, and in some cases re-epithelialization and angiogenesis among others. Thus, as the pursuit of improvement is an ongoing effort, this work presents the advances made in the treatment of skin and soft tissue infections along with their advantages and limitations, while the still remaining challenges are addressed by providing future prospects and strategies to overcome them.
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Antiinfecciosos , Infecciones de los Tejidos Blandos , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Péptidos Antimicrobianos , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/uso terapéutico , Péptidos Catiónicos Antimicrobianos/químicaRESUMEN
The purpose of this study was to evaluate the effect of 8-week ß-alanine supplementation on C-Reactive Protein (CRP), interleukin-6 (IL-6), body composition, and bio-motor abilities in elite male basketball players. Twenty male basketball players (age: 23 + 0.6 years; body mass: 78.3 + 4.8 kg; height:185.3 + 5.4 cm, %BF, 15.2 ± 4.8) volunteered to participate in this study. They were divided into a ß-alanine group (BG, N = 10) and a placebo group (PG, N = 10). All players were preparing for university competitions and had played for over five years. Players used 6.4 g/d of ß-alanine in BG and maltodextrin in PG. The participants were involved in regular basketball training three months before the study. CRP, IL-6, body composition parameters, and bio-motor abilities were measured before starting the exercises and after completing the eight-week training period. The research findings showed a significant decrease in CRP and IL-6 and an increase in anaerobic peak power between the pre-test and post-test, as well as between BG and PG groups (p < 0.05). Although the other measured factors were a relative improvement compared to the pre-test and also compared to PG, these changes were not statistically significant (p < 0.05). Eight weeks of ß-alanine supplementation ameliorated increases in IL-6 and CRP associated with in-season physical stressors in collegiate basketball players. These changes in pro-inflammatory cytokines suggest that ß-alanine supplementation may be a useful nutritional strategy for immune regulation and can also improve anaerobic performance compared to PG.
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Baloncesto , Adulto , Humanos , Masculino , Adulto Joven , Baloncesto/fisiología , beta-Alanina , Composición Corporal , Proteína C-Reactiva , Suplementos Dietéticos , Interleucina-6RESUMEN
We report the development of highly sensitive substrates with great potential as Surface-enhanced Raman scattering (SERS) spectroscopy detection platforms, consisting of nanoimprint lithography (NIL) fabricated nanotrenches in plastic and covered by nanostructured silver (Ag) films with thicknesses in the 10-100 nm range deposited by direct current (DC) sputtering. The Ag film thickness was increased by using sequential deposition times and its contribution to the obtained enhancement factor was determined. The morphological and structural properties of the metalized nanotrenches were assessed by scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Crystal violet (CV) was used as analyte to test the SERS activity of the substrates prepared with or without the nanoimprinted pattern. Our original approach was to determine the resulted SERS enhancement from the synergy of three key aspects: the Ag metallization of cheap, flexible substrates, the effect of increasing the Ag film thickness and the periodic nanotrenches imprinted by NIL as substrate. We found a dramatical contribution in the SERS signal of the periodical Ag nanopattern in comparison to the Ag film quantified by a calculated enhancement factor (EF) up to 107 in case of the SERS detection platform with a 25 nm Ag layer on top of the periodic nanotrenches. The contribution of plasmonic nanostructures contained in the Ag films as well as the contribution of the periodical nanopatterned trenches was assessed, as a cumulative effect to the first contribution. This substrate showed a considerably lower limit of detection (LOD) for SERS, down to 10 pM, much better uniformity as well as more reproducible signals in comparison with the other thicknesses of the metallic film.
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Nanoestructuras , Plata , Límite de Detección , Nanoestructuras/química , Plata/química , Espectrometría Raman/métodos , Propiedades de SuperficieRESUMEN
BACKGROUND: Despite the importance attributed to athletes' motivation in sports performance and well-being; no measures of motivation toward sport were found in the Romanian sport context. OBJECTIVE: Grounded in self-determination theory, this research aimed to adapt and to gather validity and reliability evidence supporting the use of the Behavioral Regulation in Sport Questionnaire (BRSQ) in the Romanian sport domain. METHOD: The participants were 596 Romanian professional athletes (age: M = 22.91, SD = 5.84; sports experience: M = 11.14, SD = 5.03), who 273 practiced individual sports and 323 team sports. They completed an online questionnaire survey assessing their perception of behavioral regulation, resilience and burnout in sport. RESULTS: Confirmatory factor analysis supported the six-factor correlated model, which was invariant across age and sport. Correlations among latent factors configured a simplex structure, underpinning the self-determination continuum. Average variance extracted values from .50 to .70 endorsed convergent validity. Scores for heterotrait-monotrait ratio of correlations as high as .88, as well as 95% confidence intervals of each interfactor correlation that did not include 1.00 supported discriminant validity. Values over .70 for Cronbach's alpha, McDonald's omega and Raykov's coefficients showed a good level of reliability for each factor. Linear regression analysis revealed that while intrinsic motivation, integrated regulation and identified regulation positively predicted resilience, introjected regulation, external regulation and amotivation positively predicted burnout. CONCLUSIONS: The BRSQ is shown to be a valid and reliable measure of the six types of behavioral regulation in the Romanian sport context.
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Rendimiento Atlético , Agotamiento Profesional , Humanos , Reproducibilidad de los Resultados , Rumanía , Atletas , Encuestas y CuestionariosRESUMEN
On the basis of the integrative concept of self-esteem discussed in sport-related literature, various studies refer to its importance in the context of sports activities. Self-esteem is often understood as a personality trait because it tends to be durable and stable. No accurate description is available regarding the types of sports in which subjects participated. The main purpose of the research was to identify and compare the levels of self-esteem and self-confidence of athletes practicing individual and team sports. The self-esteem and self-confidence levels were measured by the Rosenberg Self-Esteem Scale (Rosenberg 1979) and the Self-Confidence Test (Romek, 2000). All participants were males. Subjects were divided into two categories: 40 for individual sports and 40 for team sports. There were two evaluation periods: P1, the beginning of the preparation period, and P2, the beginning of the competition period. There were statistically significant differences for P1 (p < 0.002) and P2 (p < 0.003). The differences between the average values of the two periods were 5.8 points and 3.8 points, both favorable to the group of athletes who practiced individual sports. There were significant differences between the individual and team athletes in self-esteem level. Individual athletes presented a higher level of self-esteem.
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Deportes , Deportes de Equipo , Atletas , Humanos , Masculino , AutoimagenRESUMEN
The aim of the study was to identify differences in obesity-related parameters between active sports students and semi-active or sedentary students, differentiated by sex, in order to optimize health. The study sample included 286 students, of which the male experimental sample consisted of 86 active sports students, age X ± SD 21.25 ± 0.32 years; height X ± SD 181.08 ± 3.52 cm; control group consisting of 89 semi-active students aged X ± SD 21.07 ± 0.1.13 years; height X ± SD 182.11 ± 1.32. The female experimental sample includes 57 active sports students, age X ± SD 21.02 ± 0.92 years; height X ± SD 167.48 ± 1.34 cm; the control group includes 54 semi-active students aged X ± SD 21.57 ± 0.1.98 years; height X ± SD 168.42 ± 1.76. The study used a thalliometer, Tanita Health Ware software and Quantum Resonance Magnetic Analyzer equipment to investigate height (cm), Body Mass Index (BMI), muscle mass (kg, %), as well as the obesity analysis report, and componential analysis of body and nourishment. The differences registered between the samples of active and semi-active sports subjects were predominantly statistically significant for p < 0.05. The differences registered between the samples of active and semi-active sports subjects were predominantly statistically significant for p < 0.05. The most important parameters regarding obesity and body composition that registered significant differences between the two male groups were in favor of the group of active athletes: triglyceride content of abnormal coefficient 0.844 (CI95% 0.590-1.099), abnormal lipid metabolism coefficient 0.798 (CI95% 1.091-0.504), obesity degree of body (ODB %) 10.290 (CI95% 6.610-13.970), BMI 2.326 (CI95% 1.527-3.126), body fat (kg) 2.042 (CI95% 0.918-3.166), muscle volume (kg) 2.565 (CI95% 1.100-4.031), Lean body weight (kg) 2.841 (CI95% 5.265-0.418). In the case of female samples, the group of active sportswomen registered the biggest differences compared to the group of students who were significantly active in the parameters: abnormal lipid metabolism coefficient 1.063 (CI95% 1.380-0.746), triglyceride content of abnormal coefficient 0.807 (CI95% 0.437-1.178), obesity degree of body (ODB%) 8.082 (CI95% 2.983-13.181), BMI 2.285 (CI95% 1.247-3.324), body fat (kg) 2.586 (CI95% 0.905-4.267), muscle volume (kg) 2.570 (CI95% 0.154-4.985), lean body weight (kg) 4.118 (CI95% 1.160-7.077). The results of the study directly facilitate the understanding of the complexity of the impact of obesity on multiple parameters of body composition and health.
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Composición Corporal , Hombres , Índice de Masa Corporal , Femenino , Humanos , Fenómenos Magnéticos , Masculino , EstudiantesRESUMEN
Quercetin, one of the most abundant flavonoids in plant-based foods, commonly occurs in nature in various glycosylated forms. There is still a less explored aspect regarding the cause of diversity of its glycosides, depending on the sugar moiety attached. This work focuses on four wide-spread quercetin glycosides-hyperoside, isoquercitrin, quercitrin and rutin-by testing the property-tuning capacity of different sugar moieties and thus explains and predicts some of their functions in plant-based foods. The electron paramagnetic spectra of the semiquinone anion radicals of these glycosides were interpreted in terms of hyperfine coupling constants and linewidths, highlighting a clear link between spin density trends, the identity of the bound sugar, and their reactivity corroborated with their modelled structures. Redox potential and lipophilicity were connected to a specific flavonoid-enzyme interaction and correlated with their prooxidant reactivity assessed by oxidation of ferrous hemoglobin. Hyperoside and isoquercitin-galactose and glucose glycosides-exhibit the highest prooxidant reactivity owing to their lowest redox potential and lipophilicity whereas rutin and quercitrin-rutinose and rhamnose glycosides-behave vice versa. The ability of the tested glycosides to undergo HAT or SET-type reactions has also been tested using five different analytical assays, including inhibition of cytochrome c-triggered liposome peroxidation. In most cases, rutin proved to be the most unreactive of the four tested glycosides considering either steric or redox reasons whereas the reactivity hierarchy of the other three glycosides were rather assay dependent.
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Glicósidos/química , Quercetina/análogos & derivados , Rutina/química , Antioxidantes/química , Espectroscopía de Resonancia por Spin del Electrón , Electrones , Depuradores de Radicales Libres/química , Hidrógeno/química , Lípidos/química , Oxidantes/química , Oxidación-Reducción , Quercetina/química , Rutina/farmacologíaRESUMEN
In this work, we propose a novel approach to design robust microfluidic devices with integrated plasmonic transducers allowing portability, reduced analysis time through dynamic measurements and high sensitivity. Specifically, the strategy we apply involves two steps: (i) the controlled deposition of gold bipyramidal nanoparticles (AuBPs) onto a functionalized solid glass substrate and (ii) the integration of the as-fabricated plasmonic substrate into a polydimethylsiloxane (PDMS) microfluidic circuit. The localized surface plasmon resonance (LSPR) sensitivity of the plasmonic-microfluidic device was evaluated by monitoring the optical responses at refractive index changes, proving a bulk sensitivity of 243 nm RIU-1 for the longitudinal LSPR band of isolated AuBPs and 150 nm RIU-1 for the band assigned to end-to-end linked nanoparticles. A strong electric field generated in the gaps between AuBPs-due to the generation of the so-called extrinsic 'hot-spots'-was subsequently proved by the volumetric surface enhanced Raman scattering (SERS) detection of molecules in continuous flow conditions by loading the analyte into the microfluidic channel via a syringe pump. In conclusion, our miniaturized portable microfluidic system aims to detect and identify, in real-time with high accuracy, analyte molecules in laminal flow, thus providing a groundwork for further complex biosensing applications.
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BACKGROUND: High antimicrobial efficacy of short tryptophan-and arginine-rich peptides makes them good candidates in the fight against pathogens. Substitution of tryptophan and arginine by histidine could be used to modulate the peptides efficacy by optimizing their structures. METHODS: The peptide (RRWWRWWRR), reported to showed good antimicrobial efficacy, was used as template, seven new analogs being designed substituting tryptophan or arginine with histidine. The peptides' efficacy was tested against E. coli, B. subtilis and S. aureus. The cytotoxicity and hemolytic effect were evaluated and the therapeutic index was inferred for each peptide. Atomic force microscopy and molecular simulation were used to analyze the effects of peptides on bacterial membrane. RESULTS: The substitution of tryptophan by histidine proved to strongly modulate the antimicrobial activity, mainly by changing the peptide-to-membrane binding energy. The substitution of arginine has low effect on the antimicrobial efficacy. The presence of histidine residue reduced the cytotoxic and hemolytic activity of the peptides in some cases maintaining the same efficacy against bacteria. The peptides' antimicrobial activity was correlated to the 3D-hydrophobic moment and to a simple structure-based packing parameter. CONCLUSION: The results show that some of these peptides have the potential to become good candidates to fight against bacteria. The substitution by histidine proved to fine tune the therapeutic index allowing the optimization of the peptide structure mainly by changing its binding energy and 3D-hydrophobic moment. GENERAL SIGNIFICANCE: The short tryptophan reach peptides therapeutic index can be maximized using the histidine substitution to optimize their structure.
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Antiinfecciosos/farmacología , Péptidos/farmacología , Arginina , Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Hemólisis/efectos de los fármacos , Histidina , Humanos , Modelos Moleculares , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , TriptófanoRESUMEN
This work is focused on self-assembled monolayers (SAMs) fabrication, using two types of Au surfaces, by subsequent attachment of different layers in order to develop a stable platform consisting of covalent multilayer functionalized gold surfaces. The key step in the construction of SAMs is the covalent linkage to the gold surface, via an amino-thiol derivative, of a cyclooctyne unit exhibiting strained triple bonds which react fast (catalysts are not needed) and quantitatively with organic azides and enable the introduction of various chemical functionalized entities on the gold surface. The versatility of the system is demonstrated by the reaction of the cyclooctyne decorated gold surface with an azide functionalized terpyridine followed by step by step complexation with Fe(II) and another terpyridine unit resulting into a multilayer covered gold surface. The Au surfaces were characterized by XPS to determine the chemical composition of the resulting SAMs. SPR was applied for real-time monitoring of the molecular interactions that occurred on the Au surface for each deposited layer. DPN was used to direct pattern the terpyridine-ink on a pre-functionalized AuIDE electrode. The AFM topology resulted from DPN and PEIS demonstrated metal-coordinating ligand of Fe(II)-Terpy.
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Materiales Biocompatibles Revestidos/química , Oro/química , Piridinas/química , Química Clic/métodos , Hierro/química , Microscopía de Fuerza Atómica , Propiedades de SuperficieRESUMEN
Many aromatic molecules self-associate in aqueous solutions into dimers, trimers, and higher order one-dimensional aggregates. They self-assemble due to the π-π stacking interactions in supramolecular structures with a length distribution determined by the size-dependent association equilibrium constants. Due to their low solubility, in many experiments the aromatic molecules are dissolved in their cationic form. The presence of the localized positive charge promotes a new type of binding led by the cation-π interaction. Accordingly, in the case of aromatic molecules dissolved in water in their cationic form, at least two types of aggregates may appear: the rodlike aggregates stabilized by π-π stacking, and dimers coupled by the cation-π interaction. The heat exchange which accompanies the association (dissociation) processes offers the most direct way to determine the characteristic thermodynamic parameters. The heat exchange that arises at each dissociation event has been measured by isothermal titration calorimetry (ITC) on a test molecule whose self-association properties are already known: ciprofloxacin hydrochloride. The fitting protocol relies on the recently developed DK self-association model which describes in a rigorous manner the size distribution of molecular aggregates in solution.
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The interaction between stavudine, a nucleoside reverse transcriptase inhibitor and human serum albumin (HSA), was investigated by fluorescence quenching technique and isothermal titration calorimetry (ITC). A good linearity of albumin fluorescence quenching in the presence of stavudine was determined. Analyzing these data we obtained for the dissociation constant the value K(d)=(18.18 ± 0.46) × 10(-5)M. However, due to contradictory results obtained in ITC experiments, we checked the fluorescence quenching data for the inner-filter effect, the main confounding factor in the observed quenching. Based on the UV-vis absorption data we have corrected the observed fluorescence intensities and concluded, in accordance with ITC results, that stavudine binding to HSA is negligible and the observed quenching effect is entirely caused by a failure to correct for the inner-filter effect.
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Calorimetría/métodos , Albúmina Sérica/química , Albúmina Sérica/metabolismo , Espectrometría de Fluorescencia/métodos , Estavudina/química , Estavudina/metabolismo , Fluorescencia , Humanos , Unión ProteicaRESUMEN
One of the most important purposes in molecular technologies is the preparation of supramolecular structures by self-assembling processes. The aromatic molecules self-associate mainly in π-π stacked structures with an aggregate size distribution determined by the association equilibrium constants. A general expression for the equilibrium constants K(n,m) which govern the self-association of two aggregates with n and m monomers respectively has been obtained. The model predicts also the concentrations of free monomers, the concentrations of n-mers, and the total concentration of aggregates. (1)H NMR experiments have been used to illustrate the applicability of the proposed model in a particular case: π-stacking self-association of ciprofloxacin in solution.
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Ciprofloxacina/química , Sustancias Macromoleculares/síntesis química , Sustancias Macromoleculares/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Tamaño de la Partícula , TermodinámicaRESUMEN
The study aims to present a detailed theoretical investigation of noncovalent intermolecular interactions between different π-π stacking nitrogen substituted phenothiazine derivatives by applying second-order Møller-Plesset perturbation (MP2), density functional (DFT) and semiempirical theories. The conformational stability of these molecular systems is mainly given by the dispersion-type electron correlation effects. The density functional tight-binding (DFTB) method applied for dimer structures are compared with the results obtained by the higher level theoretical methods. Additionally, the optimal configuration of the investigated supramolecular systems and their self-assembling properties are discussed.
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Modelos Moleculares , Nitrógeno/química , Fenotiazinas/química , Simulación por Computador , Conformación MolecularRESUMEN
This study aims to present a detailed theoretical investigation of noncovalent intermolecular interactions between different π-π stacking phenothiazine derivatives and between different alkane chains varying from propane to decane. Second-order Møller-Plesset perturbation (MP2), coupled cluster (CC), and density functional (DFT) theories were the quantum chemistry methods used in our calculation. For MP2 and CC methods, the density-fitting and local approximations were taken into account, while in the case of DFT, the M06 and M06-2x hybrid meta-GGA exchange-correlation functionals as well as the semiempirical correction to the DFT functional for dispersion (BLYP-D) was considered. The results obtained with the aforementioned methods were compared with the potential energy curve given by the DF-SCSN-LMP2 theory considered as benchmark. For all these calculations, the correlation-consistent basis sets of cc-pVNZ (where N = D, T, Q) were used. In addition, potential energy curves built using the semiempirical PM6-D2 and the MM3 molecular force field methods were also compared with the benchmark curve and their efficiency was discussed. As the next step, several geometry conformations were investigated for both phenothiazine derivatives and alkane chain dimers. It was found that the conformational stability of these molecular systems is exclusively given by the dispersion-type electron correlation effects. The density functional tight-binding (DFTB) method applied for dimer structures was compared with the results obtained by the higher level local perturbation theory method, and based on these conclusions larger phenothiazine derivative oligomers structures were investigated. Finally, the optimal configuration of the complex molecular systems built by phenothiazine derivative, alkane chain fragments, and thiol groups was determined, and their self-assembling properties were discussed.
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Química/métodos , Fenotiazinas/química , Alcanos/química , Simulación por Computador , ADN/química , Dimerización , Electrones , Modelos Químicos , Modelos Moleculares , Conformación Molecular , Nitrógeno/química , Propano/química , Teoría CuánticaRESUMEN
Red blood cells (RBCs) scatter light mainly in the forward direction, where the scattering phase function has a narrow peak. We performed an experimental investigation into the angular distribution of light scattered by blood in the small-angle domain. A highly diluted suspension of RBCs (hematocrits in the range 5 x 10(-5)-10(-2)) was illuminated with a He-Ne laser with 633 nm wavelength. We focused our research on two main topics: the scattering efficiency of the RBCs given by the mean scattering cross section and the scattering anisotropy obtained from the angular distribution of the scattered photons. The collimated beam transmission and the angular distribution of scattered light were measured and compared with the predictions of the effective phase function model. The RBCs' mean scattering cross section and scattering anisotropy were obtained by fitting of the experimental data.
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The scattering process induced in blood by a collimated laser beam is theoretically investigated. An individual red blood cell (RBC) has a scattering phase function strongly peaked in the forward direction. For far-field experiments, the small scattering volumes can be considered as "macroscopic particles" characterized by an effective scattering phase function. Using the single-cell phase function as "input data" the angular distribution of light scattered at small angles by the whole scattering volume, containing RBCs in suspension, is calculated analytically. The angular dispersion of the light scattered by blood can be approximately described by the same formula used to characterize the light scattered by a single cell but with an effective, hematocrit-dependent anisotropy parameter.