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Achieving metal-organic frameworks (MOFs) with nonlinear optical (NLO) switching is profoundly important. Herein, the conductive MOFs Cu-TCNQ phase I (Ph-I) and phase II (Ph-II) films were prepared using the liquid-phase-epitaxial layer-by-layer spin-coating method and steam heating method, respectively. Electronic experiments showed that the Ph-II film could be changed into the Ph-I film under an applied electric field. The third-order NLO results revealed that the Ph-I film had a third-order nonlinear reverse saturation absorption (RSA) response and the Ph-II film displayed a third-order nonlinear saturation absorption (SA) response. With increases in the heating time and applied voltage, the third-order NLO response realized the reversible transition between SA and RSA. The theoretical calculations indicated that Ph-I possessed more interlayer charge transfer, resulting in a third-order nonlinear RSA response that was stronger than that of Ph-II. This work applies phase-transformed MOFs to third-order NLO switching and provides new insights into the nonlinear photoelectric applications of MOFs.
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Central metal exchange can innovatively open the cavity of metal-organic frameworks (MOFs) by alternating the framework topology. Here, the single-crystal-to-single-crystal (SC-SC) transformation is reported from a Co-based MOF {[Co1.25 (HL)0.5 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -OH)0.25 (H2 O)]·0.125 Co·0.125 L·10.25H2 O}n (Co-MOF, L = 5,5'-(1H-2,3,5-triazole-1,4-diyl)diisophthalic acid) into two novel MOF materials, {[Cu1.75 L0.75 (Pz-NH2 )0.125 (µ3 -O)0.125 (µ2 -OH)0.25 (H2 O)0.375 ]â¢3CH3 CN}n (Cu-MOF) and {[Zn1.75 L0.625 (Pz-NH2 )0.25 (µ3 -O)0.25 (µ2 -O)0.25 (H2 O)1.25 ]â¢4CH3 CN}n (Zn-MOF), through exchanging the Co2+ in the MOF into Cu2+ or Zn2+ , respectively. The free Co2+ and L4- in the Co-MOF channels fuse with the skeleton during the CoâCu and CoâZn exchange processes, leading to the expansion of the channel space and the transformation of the secondary building units (SBUs) to form an adjustable skeleton. The nonlinear optical response results show that the MOFs generated by the exchange of the central metal exhibit different saturable absorption and the self-focusing effect. In addition, loading polypyrrole (PPy) into the MOFs can not only improve the stability of the MOFs but also further optimize the nonlinear optical behavior. This work suggests that SC-SC central metal exchange and the introduction of polymer molecules can tune the nonlinear optical response, which provides a new perspective for the future study of nonlinear optical materials.
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Upon the secondary contact of populations, speciation with gene flow is greatly facilitated when the same pleiotropic loci are both subject to divergent ecological selection and induce non-random mating, leading to loci with this fortuitous combination of functions being referred to as 'magic trait' loci. We use a population genetics model to examine whether 'pseudomagic trait' complexes, composed of physically linked loci fulfilling these two functions, are as efficient in promoting premating isolation as magic traits. We specifically measure the evolution of choosiness, which controls the strength of assortative mating. We show that, surprisingly, pseudomagic trait complexes, and to a lesser extent also physically unlinked loci, can lead to the evolution of considerably stronger assortative mating preferences than do magic traits, provided polymorphism at the involved loci is maintained. This is because assortative mating preferences are generally favoured when there is a risk of producing maladapted recombinants, as occurs with non-magic trait complexes but not with magic traits (since pleiotropy precludes recombination). Contrary to current belief, magic traits may not be the most effective genetic architecture for promoting strong premating isolation. Therefore, distinguishing between magic traits and pseudomagic trait complexes is important when inferring their role in premating isolation. This calls for further fine-scale genomic research on speciation genes.
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Comunicación Celular , Flujo Génico , Genómica , Fenotipo , Polimorfismo GenéticoRESUMEN
Strong coupling provides a powerful way to modify the nonlinear optical properties of materials. The coupling strength of the state-of-the-art strongly coupled systems is restricted by a weak-field confinement of the cavity, which limits the enhancement of the optical nonlinearity. Here, we investigate a strong coupling between Mie resonant modes of high-index dielectric nanocavities and an epsilon-near-zero mode of an ultrathin indium tin oxide film and obtain an anticrossing splitting of 220 meV. Static nonlinear optical measurements reveal a large enhancement in the intensity-independent effective optical nonlinear coefficients, reaching more than 3 orders of magnitude at the coupled resonance. In addition, we observe a transient response of â¼300 fs for the coupled system. The ultrafast and large optical nonlinear coefficients presented here offer a new route towards strong coupling-assisted high-speed photonics.
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The development of metal-organic frameworks (MOFs) with nonlinear optical (NLO) properties is of pronounced significance for optical devices. Herein, a series of 2D MOFs ZnTPyP(M) (TPyP = 5,10,15,20-tetrakis(4-pyridyl)porphyrin, M = Cu, Ni, Mn, H2) films with [010]-orientation growth composed of ultrathin nanosheets from a pyridylporphyrinic ligand are first obtained by using a liquid-phase epitaxial (LPE) layer-by-layer (lbl) growth approach. ZnTPyP(M) films show a giant nonlinear optical limiting (OL) response and can be modulated by tuning the type of metalloporphyrinic ligands. As a result, ZnTPyP(Cu) film exhibits the highest nonlinear absorption coefficient of 5.7 × 10-6 m/W compared to other reported NLO materials. Density functional theory calculations were consistent with the experimental results, revealing that the tunable π-π* local excitation and the increased delocalization of the metalloporphyrinic group regulate the NLO performance of ZnTPyP(M) films. These findings provide new insight into the effect of 2D porphyrinic MOFs toward the NLO response and offer new film candidates for nonlinear OL application.
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Estructuras Metalorgánicas , Metaloporfirinas , Porfirinas , Ligandos , Compuestos de ZincRESUMEN
A high-yielding click reaction was used to synthesize a series of highly conjugated, symmetrical, as well as asymmetrical compounds with a benzene core. Cyclic voltammetry and ultraviolet/visible absorption spectroscopy were carried out, and proved that the side groups of the benzene derivatives played an important role in the energy gaps, and affected the third-order non-linear optical response. The maximum absorption wavelength of the series of benzene derivatives showed an obvious red-shift. Moreover, the addition of resilient electron-withdrawing groups significantly narrowed the energy levels as compared with precursors. The third-order nonlinear properties of this benzene derivative were tested by the Z-scan technique. The expected properties of this series of molecules were obtained, and it was found that the series of molecules undergoes a transition from reverse saturable absorption to saturable absorption, which has certain reference significance for a nonlinear optical field.
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A novel 4(1H) quinolinone derivative (QBCP) was synthesized and characterized with single crystal X-ray diffraction. Hirshfeld surfaces (HS) analyses were employed as a complementary tool to evaluate the crystal intermolecular interactions. The molecular global reactivity parameters of QBCP were studied using HOMO and LUMO energies. In addition, the molecular electrostatic potential (MEP) and the UV-Vis absorption and emission spectra were obtained and analyzed. The supermolecule (SM) approach was employed to build a bulk with 474,552 atoms to simulate the crystalline environment polarization effect on the asymmetric unit of the compound. The nonlinear optical properties were investigated using the density functional method (DFT/CAM-B3LYP) with the Pople's 6-311++G(d,p) basis set. The quantum DFT results of the linear polarizability, the average second-order hyperpolarizability and the third-order nonlinear susceptibility values were computed and analyzed. The results showed that the organic compound (QBCP) has great potential for application as a third-order nonlinear optical material.
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Teoría Cuántica , Cristalografía por Rayos X , Modelos Moleculares , Conformación Molecular , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad EstáticaRESUMEN
A student asked, "What is pastoral care amid the COVID-19 pandemic?" The student and the professor embarked on a conversational journey to explore the layers of suffering during the pandemic that prompted the question and to interpret the neoliberal characteristics of the relational pains in the experience. Through the participatory case study of this conversation, this article puts the pandemic experience of the student in dialogue with the Matthean passage on the vineyard workers to expose the limits of the neoliberal rationality that feeds into the suffering during the pandemic. The ensuing theological reflection culminates in a conversation about the understanding of the Matthean evil eye, Emmanuel Levinas's understanding of the face, and Bruce Roger-Vaughn's concept of third-order suffering. The reflection concludes with an answer to the question about pastoral care during COVID-19.
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Understanding the correlation between crystal structure and thermal conductivity in semiconductors is very important for designing heat-transport-related devices, such as high-performance thermoelectric materials and heat dissipation in micro-nano-scale devices. In this work, the lattice thermal conductivity ( κ L ) of the cage-like compounds Cu3 VSe4 and Cu3 NbSe4 was investigated by experimental measurements and first-principles calculations. The experimental κ L of Cu3 NbSe4 is approximately 25 % lower than that of Cu3 VSe4 at 300â K. The relevant important physical parameters, including the sound velocity, heat capacity, weighted phonon phase space (W), and third-order force constants along with atomic mass were theoretically analyzed. It is found that W is the dominant parameter in determining the κ L , and the other factors only play a minor role. The physical origin is the relatively "soft" lattice of Cu3 NbSe4 with heavier atomic mass. This research provides deep insight into the correlation between the thermal conductivity and crystal structure and paves the way for discovering high-performance thermal management device and thermoelectric materials with intrinsically low κ L .
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This study is the first to develop and optimize a method for the simultaneous determination of chlorthalidone (CLT) and telmisartan (TEL) in, human plasma samples as well as in their newly released pharmaceutical tablet form, (Telmikind-CT 40®). The method is based on measuring fluorescence intensity, employing synchronous fluorescence mode coupled to third-order derivative signal processing, 0.5% w/v cetyl trimethyl ammonium bromide was used as cationic surfactant to enhance the fluorescence signal intensity and improve method sensitivity. The third-order derivative synchronous spectra of CLT and TEL are well separated with two zero-crossing points which allowed for the determination of CLT and TEL at 362 nm and 351 nm, respectively. Different experimental parameters were carefully investigated and optimized, calibration curves were constructed over concentration ranges of 20-1200 ng.mL-1 and 5-800 ng.mL-1 for CLT and TEL respectively. The developed method is simple and rapid, analytical parameters were validated according to ICH guidelines and high sensitivity was achieved as represented by limits of detection (LOD) of 4.69 and 1.58 ng.mL-1 for CLT and TEL respectively.
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Análisis Químico de la Sangre/métodos , Clortalidona/sangre , Telmisartán/sangre , Combinación de Medicamentos , Humanos , Límite de Detección , Espectrometría de FluorescenciaRESUMEN
Third-order equations are well known for determining sagittal and tangential powers of a thin lens, corresponding to an eye rotating behind a lens to view objects away from the optical axis of the lens. These equations are referenced to the back surface of the lens and do not take into account the peripheral thickness of the lens. They do not give the same results as finite raytracing at small angles in which powers are referenced to the vertex sphere, which is the same distance from the centre-of-rotation for all object angles. Modified forms of the third-order sagittal and tangential image vergence error equations are developed to overcome the discrepancies. These are used to determine Tscherning ellipses for zero oblique astigmatism and zero mean oblique power error. While solutions to oblique astigmatism are not affected by the modifications, there are considerable changes to mean oblique error solutions.
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Astigmatismo/terapia , Anteojos/tendencias , Modelos Teóricos , Óptica y Fotónica , Refracción Ocular/fisiología , Astigmatismo/fisiopatología , Diseño de Equipo , HumanosRESUMEN
In this paper, the possibility of using nonlinear ultrasonic guided waves for early-life material degradation in metal plates is investigated through both computational modeling and study. The analysis of the second harmonics of Lamb waves in a free boundary aluminum plate, and the internal resonance conditions between the Lamb wave primary modes and the second harmonics are investigated. Subsequently, Murnaghan's hyperelastic model is implemented in a finite element (FE) analysis to study the response of aluminum plates subjected to a 60 kHz Hanning-windowed tone burst. Different stages of material degradation are reflected as the changes in the third order elastic constants (TOECs) of the Murnaghan's model. The reconstructed degradations match the actual ones well across various degrees of degradation. The effects of several relevant factors on the accuracy of reconstructions are also discussed.
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Ondas Ultrasónicas , Vibración , Animales , Simulación por Computador , Análisis de Elementos Finitos , Ovinos , TomografíaRESUMEN
In the paper, we provide sufficient conditions for the oscillatory and asymptotic behavior of a new type of third-order nonlinear dynamic equations with mixed nonlinear neutral terms. Our theorems not only improve and extend existing theorems in the literature but also provide a new approach as far as the nonlinear neutral terms are concerned. The main results are illustrated by some particular examples.
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Third-order nonlinear two-wave dynamical X-ray diffraction in a crystal is considered. For the Laue symmetrical case of diffraction a new exact solution is obtained. The solution is presented via Jacobi elliptic functions. Two input free parameters are essential: the deviation parameter from the Bragg exact angle and the intensity of the incident wave. It is shown that the behavior of the field inside the crystal is determined by the sign of a certain combination of these parameters. For negative and positive signs of this combination, the wavefield is periodic and the nonlinear Pendellösung effect takes place. For the nonlinear Pendellösung distance the appropriate expressions are obtained. When the above-mentioned combination is zero, the behavior of the field can be periodic as well as non-periodic and the solution is presented by elementary functions. In the nonperiodic case, the nonlinear case Pendellösung distance tends to infinity. The wavefield diffracts and propagates in a medium, whose susceptibility is modulated by the amplitudes of the wavefields. The behavior of the wavefield can be described also by an effective deviation from the Bragg exact angle. This deviation is also a function of the wavefields.
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The polar solvents dependent linear and third-order nonlinear optical (NLO) characteristics of acid blue 3 (AB 3) dye has been reported in this paper. A low power continuous wave (CW) diode laser working at 635 nm wavelength was used to perform the Z-scan experiments in the present study. AB 3 dye was dissolved with different polar solvents of 1-propanol, ethanol, dimethyl sulfonate (DMSO) and water at a concentration of 0.01 mM. The nonlinear index of refraction (n2) of AB 3 dye was ascribed to self-defocusing effect, and nonlinear coefficient of absorption (ß) signifies the behaviors of saturable and reverse saturable absorption. The real and imaginary components of the third-order NLO susceptibility of AB 3 dye in the present polar solvents have been measured to be of the order of 10â6 esu. The influence of polar solvents on third-order NLO susceptibility of the dye sample studied has been discussed. The second-order hyperpolarizability (γ) of AB 3 dye has also been studied and estimated to be of the order of 10â30 esu. The experimental results suggest that AB 3 dye may be a promising candidate for applications in nonlinear optics.
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The study of heat and electroosmotic characteristics in the flow of a third-order fluid regulated by peristaltic pumping is examined by using governing equations, i.e., the continuity equation, momentum equation, energy equation, and concentration equation. The wavelength is considered long compared to its height and a low Reynolds number is assumed. The velocity slip condition is employed. Analytical solutions are performed through the perturbation technique. The expressions for the dimensionless velocity components, temperature, concentration, and heat transfer rate are obtained. Pumping features were computed numerically for discussion of results. Trapping and heat transfer coefficient distributions were also studied graphically. The findings of the present study can be applied to design biomicrofluidic devices like tumor-on-a-chip and organ-on-a-chip.
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Electroósmosis/instrumentación , Calor , Hidrodinámica , Modelos TeóricosRESUMEN
AIM: The purpose of the study was to perform intraoperative assessment of blood flow in coronary bypass grafts of the 'first' and 'third' order according to Calafiore A.M. with the help of the TTFM technique and to compare the obtained results. PATIENTS AND METHODS: This retrospective, single-centre study enrolled a total of 222 patients subjected to coronary artery bypass grafting (CABG) from January to November 2017. Depending on the type of bypass grafting of the posterior interventricular artery (PIVA), the patients were divided into 2 groups. Group One consisted of 108 patients undergoing bypass grafting of the PIVA with the help of combined Y-grafts from the right internal thoracic artery (RTIA). Group Two was composed of 114 patients subjected to autovenous coronary artery bypass grafting of the PIVA. Blood flow was assessed with the help of the VeriQ MediStim® flowmeter after termination of extracorporeal circulation (ECC), at systolic pressure of 100-110 mm Hg. The parameters of blood flow were assessed using the 1.5- and 2-mm probes. In a specially designed protocol we registered the type of the shunt, the bypassed artery, and values of flowmetry parameters. We also evaluated the pattern of the flowmetric curve according to Takemi Handa et al. RESULTS: The obtained findings revealed a statistically significant difference in the values of Qmean (p=0.001), with the PI values in the groups not statistically differing (p=0.14). Thus, in patients with similar parameters influencing the volumetric velocity of blood flow (the degree of proximal stenosis, diameter of the bypassed artery, mean systolic AP and HR) the value of Qmean was higher in the group with coronary artery bypass grafting (CABG), i. e., in the group of the 'first-order' conduits. Therefore, an autovein directly anastomosed to the aorta experiences grater haemodynamic overload, which completely confirms the theory of Calafiore A.M. CONCLUSION: First-order conduits (CABG) appear to experience greater wall strain because of greater haemodynamic overload as compared with third-order conduits (Y-grafts). A composite Y-graft may be an alternative technique of bypass grafting of the basin of the right coronary artery (RCA). A composite Y-graft has greater resistance to wall shear stress than an autovein anastomosed to the aorta.
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Puente de Arteria Coronaria , Arterias Mamarias , Angiografía Coronaria , Circulación Coronaria , Vasos Coronarios/cirugía , Circulación Extracorporea , Humanos , Estudios Retrospectivos , Grado de Desobstrucción VascularRESUMEN
We contend that the field of family therapy is undergoing a notable shift from second- to third-order thinking. We offer theoretical support and examples to demonstrate how third-order thinking provides a framework for integrating heightened sociocultural attunement into family therapy practice. We discuss the importance of third-order thinking relative to being prepared to invite families into third-order change. Finally, we offer a case example to show specific guidelines for third-order practice.
Afirmamos que el ámbito de la terapia familiar está sufriendo un cambio notable porque está pasando del pensamiento de segundo orden al pensamiento de tercer orden. Ofrecemos respaldo teórico y ejemplos para demostrar cómo el pensamiento de tercer oden ofrece un marco para integrar una mayor sensibilización sociocultural en la práctica de la terapia familiar. Debatimos la importancia del pensamiento de tercer orden relativa a estar preparados para invitar a las familias al cambio hacia el tercer orden. Finalmente, ofrecemos el ejemplo de un caso para mostrar pautas específicas sobre la práctica del tercer orden.
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Medicina Familiar y Comunitaria/métodos , Terapia Familiar/ética , Teoría Psicológica , Justicia Social/psicología , Humanos , Poder PsicológicoRESUMEN
In the present article, we related the analytical solution of the fractional-order dispersive partial differential equations, using the Laplace-Adomian decomposition method. The Caputo operator is used to define the derivative of fractional-order. Laplace-Adomian decomposition method solutions for both fractional and integer orders are obtained in series form, showing higher convergence of the proposed method. Illustrative examples are considered to confirm the validity of the present method. The fractional order solutions that are convergent to integer order solutions are also investigated.
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First to fourth-order branches of the uterine artery in sexually mature female Wistar rats were studied by biomicroscopy. After administration of a CO donor hemin (60 mM), the diameters of large uterine branches with a well-developed muscle layer markedly increased, while the increase in diameter of small vessels with one often interrupted layer of smooth muscle cells increased insignificantly. Zinc protoporphyrin IX (30 mM) in all cases blocked this effect. However, zinc protoporphyrin IX does not affect NO-mediated reaction of the branches of the uterine artery caused by administration of L-arginine (60 mM), and L-NAME did not significantly affect reactivity of uterine artery branches associated with the hemoxygenase-CO system. In contrast to NO, CO produced less potent and rapid, but more sustained effect. The target for the hemoxygenase-CO system is mainly arteries with developed muscular layer, while the target for the NO synthase-NO is small vessels where endothelium plays a Rdecisive role in the regulation of vasomotor reactions.