RESUMO
Modifying the optical and electronic properties of crystalline organic thin films is of great interest for improving the performance of modern organic semiconductor devices. Therein, the statistical mixing of molecules to form a solid solution provides an opportunity to fine-tune optical and electronic properties. Unfortunately, the diversity of intermolecular interactions renders mixed organic crystals highly complex, and a holistic picture is still lacking. Here, we report a study of the optical absorption properties in solid solutions of pentacene and tetracene, two prototypical organic semiconductors. In the mixtures, the optical properties can be continuously modified by statistical mixing at the molecular level. Comparison with time-dependent density functional theory calculations on occupationally disordered clusters unravels the electronic origin of the low energy optical transitions. The disorder partially relaxes the selection rules, leading to additional optical transitions that manifest as optical broadening. Furthermore, the contribution of diabatic charge-transfer states is modified in the mixtures, reducing the observed splitting in the 0-0 vibronic transition. Additional comparisons with other blended systems generalize our results and indicate that changes in the polarizability of the molecular environment in organic thin-film blends induce shifts in the absorption spectrum.
RESUMO
A differential equation is derived for the calculation of the wave aberration of an axial bundle of rays affected by spherical aberration. The solution of the derived equation is analyzed, and the influence of the radius of the reference sphere on the value of the wave aberration is presented. The approximate formula for wave aberration is obtained, which allows the splitting of the wave aberration into a part relative to an infinitely distant reference sphere and a part showing the dependence of the wave aberration on the radius of the reference sphere. Furthermore, the case of third-order and fifth-order spherical aberration is investigated, and the formulas for the calculation of the Strehl definition for the case of small aberrations are derived. The accuracy of the approximated formulas for the wave aberration is analyzed in an example.
RESUMO
Disruption of the thyroid hormone (TH) system is connected with diverse adverse health outcomes in wildlife and humans. It is crucial to develop and validate suitable in vitro assays capable of measuring the disruption of the thyroid hormone (TH) system. These assays are also essential to comply with the 3R principles, aiming to replace the ex vivo tests often utilised in the chemical assessment. We compared the two commonly used assays applicable for high throughput screening [Luminol and Amplex UltraRed (AUR)] for the assessment of inhibition of thyroid peroxidase (TPO, a crucial enzyme in TH synthesis) using several cell lines and 21 compounds from different use categories. As the investigated cell lines derived from human and rat thyroid showed low or undetectable TPO expression, we developed a series of novel cell lines overexpressing human TPO protein. The HEK-TPOA7 model was prioritised for further research based on the high and stable TPO gene and protein expression. Notably, the Luminol assay detected significant peroxidase activity and signal inhibition even in Nthy-ori 3-1 and HEK293T cell lines without TPO expression, revealing its lack of specificity. Conversely, the AUR assay was specific to TPO activity. Nevertheless, despite the different specificity, both assays identified similar peroxidation inhibitors. Over half of the tested chemicals with diverse structures and from different use groups caused TPO inhibition, including some widespread environmental contaminants suggesting a potential impact of environmental chemicals on TH synthesis. Furthermore, in silico SeqAPASS analysis confirmed the high similarity of human TPO across mammals and other vertebrate classes, suggesting the applicability of HEK-TPOA7 model findings to other vertebrates.
Assuntos
Iodeto Peroxidase , Iodeto Peroxidase/antagonistas & inibidores , Iodeto Peroxidase/metabolismo , Iodeto Peroxidase/genética , Humanos , Animais , Ratos , Células HEK293 , Luminol , Ensaios de Triagem em Larga Escala/métodos , Oxazinas , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Linhagem Celular , Proteínas de Ligação ao Ferro/metabolismo , Autoantígenos/metabolismo , Disruptores Endócrinos/toxicidadeRESUMO
A theoretical analysis of an afocal compensator of the secondary longitudinal chromatic aberration is provided. Such a compensator is able to compensate for chromatic aberration of an achromatic optical system and make an apochromatic correction of the system. The parameters of the proposed chromatic aberration compensator are described and the principle is presented in examples.
RESUMO
An algebraic method for finding fundamental parameters of a starting design of a two-element double-sided telecentric lens is introduced in this work. The telecentric lens is formed by two objectives composed of an afocal meniscus lens followed by a cemented doublet. It is used the third-order aberration theory to find the fundamental parameters of the starting configuration of a given optical system. The method gives results which make possible to obtain a good initial design of such a telecentric lens for further optimization using optical design software. The proposed method is presented on an example of finding initial design parameters of the double-sided telecentric lens.
RESUMO
This work introduces an algebraic method of the calculation of an initial design of a two-element optical system composed of a thick afocal meniscus lens and a thin lens element, which can be formed, for example, by a cemented doublet. The third-order aberration theory is used to find the fundamental parameters of the starting configuration of a given optical system. The method gives results that make it possible to obtain a good starting design for further optimization of such imaging systems using optical design software. The proposed method is presented on two examples of finding the initial design parameters of the objective with an afocal meniscus lens and a cemented doublet.
RESUMO
An algebraic method of an initial design of the aplanatic cemented doublet with a unit focal length is described. Based on the third-order aberration theory, algebraic equations are derived for calculating the design parameters of an aplanatic thin cemented doublet with spherical surfaces and aspherical surfaces of the second degree. These equations make it easy to determine whether there exists a real solution of the doublet design for required parameters. The results of the calculations of selected cemented doublet solutions are presented in the examples. The obtained parameters can be used as the starting solution for the final optimization of doublet designs.
RESUMO
A method for the algebraic calculation of paraxial design parameters of a telecentric f-theta lens is described. Moreover, a third-order aberration analysis is performed for a telecentric f-theta lens composed of two optical elements. The method can be used to calculate the starting optical design of telecentric f-theta lenses, which can be used, for example, in laser material processing, optical imaging systems, and optical metrology. The initial design parameters then can be used for further optimization in optical design software.
RESUMO
We describe an analytic method of the initial design of microscope objectives with a long working distance. The optical system of a microscope objective is composed of two thin optical elements and a frontal optical element from several thick lenses. The paper describes formulas that make it possible to calculate fundamental parameters of the objective, namely Seidel aberration coefficients, radii of curvature, refractive indices of individual lenses of the microscope objective, etc. The proposed method of calculation of the initial design parameters of the microscope objective, which is based on the theory of aberrations of the third order and chromatic aberrations of the first order, enables us to obtain a good starting design for further optimization using optical design software. The method of the design is presented in an example of the microscope objective with a long working distance.
RESUMO
The immune system plays an important role in many processes of human reproduction. During pregnancy, mother's body has to accept the semialogenic fetus, therefore the role of immune processes has a high importance. Tolerance of the fetus by the mother's immune system is ensured by a complex of immune mechanisms, the knowledge of which brings us to the new insights into human reproduction processes and in seeking of new ways to modulate immunity in repeated embryo implantation failures, miscarriages, premature births, preeclampsia, and other fertility disorders and pregnancy complications. The review article is a summary of current possibilities of immunological laboratory diagnostics in reproductive immunology, presents indications for these tests and their interpretation, and mentions possible methods of therapeutic immune intervention.
Assuntos
Infertilidade Feminina , Complicações na Gravidez , Nascimento Prematuro , Implantação do Embrião , Feminino , Humanos , Sistema Imunitário , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , GravidezRESUMO
Natural product chemistry, microbiology, and food, human, and plant metabolomics represent a few sources of complex metabolomics data generated by mass spectrometry. Among the medley of software tools used to handle these data sets, no universal tool can qualitatively, quantitatively, or statistically address major biological questions or tasks. CycloBranch 2, an open and platform-free software, at least now provides the de novo generation of molecular formulas of unknown compounds in both liquid chromatography/mass spectrometry and mass spectrometry imaging datafiles. For imaging files, this database-free approach was documented in the bimodal image fusion and characterization of three small molecules, including metallophores. The fine isotope ratio data filtering step distinguished 34S/13C2 and 41K/13C2 features. The standalone software package is implemented in C++ and can be downloaded from https://ms.biomed.cas.cz/cyclobranch/ and used under GNU General Public License.
Assuntos
Produtos Biológicos/análise , Software , Cromatografia Líquida , Bases de Dados Factuais , Espectrometria de Massas , Peso MolecularRESUMO
There is a growing interest in utilizing the distinctive material properties of organic semiconductors for spintronic applications. Here, we explore the injection of pure spin current from Permalloy into a small molecule system based on dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) at ferromagnetic resonance. The unique tunability of organic materials by molecular design allows us to study the impact of interfacial properties on the spin injection efficiency systematically. We show that both the spin injection efficiency at the interface and the spin diffusion length can be tuned sensitively by the interfacial molecular structure and side chain substitution of the molecule.
RESUMO
Among the nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are some of the most hazardous substances to public health, mainly because of their carcinogenicity and oxidative potential. Despite these concerns, the concentrations and fate of NPAHs and OPAHs in the atmospheric environment are largely unknown. Ambient air concentrations of 18 NPAHs, 5 quinones, and 5 other OPAHs were determined at two urban and one regional background sites in central Europe. At one of the urban sites, the total (gas and particulate) concentrations of Σ10OPAHs were 10.0 ± 9.2 ng/m3 in winter and 3.5 ± 1.6 ng/m3 in summer. The gradient to the regional background site exceeded 1 order of magnitude. Σ18NPAH concentrations were typically 1 order of magnitude lower than OPAHs. Among OPAHs, 9-fluorenone and (9,10)-anthraquinone were the most abundant species, accompanied by benzanthrone in winter. (9,10)-Anthraquinone represented two-thirds of quinones. We found that a large fraction of the target substance particulate mass was carried by submicrometer particles. The derived inhalation bioaccessibility in the PM10 size fraction is found to be ≈5% of the total ambient concentration of OPAHs and up to ≈2% for NPAHs. For 9-fluorenone and (9,10)-anthraquinone, up to 86 and 18%, respectively, were found at the rural site. Our results indicate that water solubility could function as a limiting factor for bioaccessibility of inhaled particulate NPAHs and OPAHs, without considerable effect of surfactant lipids and proteins in the lung lining fluid.
Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Europa (Continente) , Humanos , Nitratos , Material ParticuladoRESUMO
This work describes a procedure for an analytical calculation of the point spread function (PSF) of an optical system affected by defocus and spherical aberration. Explicit formulas are derived for the approximate calculation of the PSF of an optical system with spherical aberration up to the ninth order. Application of the derived formulas is performed on an example of optical systems with spherical aberration up to the third order.
RESUMO
This work describes a method for determination of a paraxial focal length of optical systems using measurements of the Strehl definition. The influence of spherical aberration on the value of the measured effective focal length of an optical system is analyzed, and a method is proposed for an elimination of this influence and determination of the paraxial focus position and the paraxial focal length of a lens from the measurement of the effective focal length and the Strehl definition.
RESUMO
An analysis and a description of methods for a paraxial design of rifle scopes with a four-element image-erecting zoom system is performed. It is described a method of the calculation of basic design parameters of the rifle scope with the four-element image-erecting zoom system, where two inner elements are movable for ensuring zooming of the rifle scope. The method is demonstrated on two examples of the rifle scope design with the zoom factor 10×. Moreover, the possibility to design the rifle scope with the fixed position of the exit pupil using the four-element image-erecting zoom system with three movable elements is analyzed. The method of the initial paraxial design is demonstrated on two examples of the calculation of the basic rifle scope design parameters. The calculated parameters from proposed methods can be used in the aberration analysis and the optimization of the rifle scope parameters in optical design software.
RESUMO
A method is proposed for calculation of initial parameters of a three-element zoom lens with an identical position of object and image principal planes of the optical system and approximately zero Petzval sum. Such an optical system has a fixed position of its optical center, which does not depend on object distance. The proposed method makes it possible to determine focal length values of individual elements and trajectories of their movements during zooming. The analysis is presented on examples of the calculation of parameters of such optical systems. These systems could be useful in optical measuring methods, photogrammetry, and machine vision techniques.
RESUMO
By a detailed analysis of the dependence of aberrations on the numerical aperture and the field of view of the optical system, it is possible to find such values of the numerical aperture and the field of view, where the residual wave aberration is zero. These values can be called correction zones. Our work presents a theoretical analysis of the described problem, and general formulas are derived for the expression of wave aberration coefficients using correction zones for astigmatism and field curvature of the third and fifth order. Finally, an analysis of optimum values of correction zones and the optimum position of the image plane has been performed using derived equations with respect to maximization of the Strehl definition. The analysis of the correction zone and the position of the image plane is presented on two examples of the same optical system, where the image plane is located either in the paraxial image plane or in the optimum image plane.
RESUMO
A theory of an optical center of a camera lens is described. The concept of an optical center (a camera center) is used widely in various methods dedicated to the calibration of optical imaging and measuring systems in photogrammetry, computer vision, triangulation sensors, fringe projection techniques, surveying, and machine vision, where the so-called pinhole camera model is used as the camera's basic model. It is shown that the optical center of the optical system with a fixed position does not exist generally, even for an ideal optical system. The optical center can be defined unambiguously for an ideal lens only for one specific object distance in general. Moreover, equations are derived for the calculation of initial design parameters of the three-element optical system composed of thin lens elements having the identical position of object and image principal planes. Such optical systems will have a fixed-position optical center, which does not depend on the object distance. The analysis was presented on several examples of the calculation of parameters of these optical systems.
RESUMO
The formulas are derived for calculation of the third-order aberration (Seidel) coefficients for a thick spherical lens in air with a given value of its focal length and for an object at infinity in this paper. The explicit analytic dependence of individual aberration coefficients on a lens thickness is derived. Equations were described for the re-calculation of aberration coefficients for a different value of focal length and different values of entrance pupil and object positions. Such formulas make it possible to analyze analytically an influence of the lens thickness on lens aberration properties and the replacement of a thin lens optical system by a thick lens model.