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Existen diversas formas de evaluar el músculo esquelético. Una herramienta que ha ganado relevancia es la evaluación ecográfica. Esta, permite medir el grosor muscular (GM) y el ángulo de penación (AP). Por otra parte, en la formación inicial de los Kinesiólogos es importante realizar el ejercicio de la confiabilidad en la medición en relación al experto. un procedimiento diagnóstico. Así, el objetivo de este estudio es determinar la confiabilidad inter-evaluador en la medición del GM y el AP, a través de la evaluación ecográfica, entre un experto y un kinesiólogo en formación. La capacitación contó de tres fases; el ciclo teórico, el ciclo práctico y el proceso de confiabilidad. Para este último, se realizaron 10 pruebas para cada una de las mediciones GM 1, GM 2 y GM 3 y de AP. La confiabilidad inter-evaluador en la medición de GM es buena a excelente en los tres intentos GM1 (ICC=0,81; p=0,001), GM2 (ICC=0,86; p<0,001), GM3 (ICC=0,88;<0,001). Por su parte, la confiabilidad del AP fue pobre a regular (ICC=0,21; p=0,143. Las conclusiones de esta investigación indican que existe una excelente confiabilidad inter evaluador en la medición de GM. No así, en la medición de AP, por lo que se sugiere incrementar las horas prácticas en el proceso de aprendizaje de esta medida.
SUMMARY: Skeletal muscle can be assessed in a number of different ways. Consequently, ultrasound evaluation has become a relevant diagnostic tool. This procedure allows measuring muscle thickness (MT) and pennation angle (PA). Furthermore, during the initial training of physical therapists it is important in a diagnostic procedure, to exercise reliability in measurement in comparison to the expert. Therefore, the objective of this study is to determine the inter-rater reliability in the measurement of MT and PA, through ultrasound evaluation, between an expert and a physical therapist in training. This training was comprised of three phases: The theoretical cycle, the practical cycle and the reliability process. For the latter, ten different tests were performed for each of the MT 1, MT 2 and MT 3 and PA measurements. Inter-rater reliability in the MT measurement was good to excellent in the three attempts MT1 (ICC=0.81; p=0.001), MT2 (ICC=0.86; p<0.001), MT3 (ICC=0. 88;<0.001). On the other hand, reliability of the PA was poor to fair (ICC=0.21; p=0.143. In conclusion, this research indicates that there is excellent inter-rater reliability in the measurement of MT. This does not however apply to the measurement of PA. It is therefore suggested that practical hours during the learning process of this measure be increased.
Assuntos
Humanos , Ultrassonografia/métodos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Variações Dependentes do Observador , Reprodutibilidade dos TestesRESUMO
Electron and hole transport characteristics were evaluated for perylene-based and pyrene-based compounds using electron-only and hole-only devices. The perylene presented a columnar hexagonal liquid crystal phase at room temperature with strong molecular π-stacking inside the columns. The pyrene crystallizes bellow 166 °C, preserving the close-packed columnar rectangular structure of the mesophase. Photophysical analysis and numerical calculations assisted the interpretation of positive and negative charge carrier mobilities obtained from fitting the space charge limited regime of current vs voltage curves. The pyrene-based material demonstrated an electron mobility two orders of magnitude higher than the perylene one, indicating the potential of this class of materials as electron transporting layer.
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Three tetraaryl-1,4-dihydropyrrolo[3,2-b]pyrrole derivatives containing different number of long alkoxy chains (2, 4 and 6) were synthesized, characterized and applied in Organic Light Emitting Diodes (OLEDs). The compounds showed good emission properties with Photoluminescence Quantum Yields (PLQYs) higher than 80 % in solution and 50 % in solid state (thin film). The solvatochromism results revealed a pronounced vibronic emission in methylcyclohexane and toluene, characterized by two distinct sharp emission peaks and a small redshift in the following order: methylcyclohexane>toluene>dichloromethane>tetrahydrofuran>acetonitrile. Also, the compounds formed aggregates with redshifted emission, which can be attributed to excimer formation. This phenomenon was observed in solutions containing 90 % water and with the concentration variation in methylcyclohexane (MCH). Compounds with a greater number of peripheral chains showed the capacity to keep hexagonal columnar organization in films after fast cooling from liquid state. OLEDs fabricated with these compounds showed turn-on voltages lower than 4.0â V, with luminance higher than 1400â cd m-2 , electroluminescence spectra with Full Width at Half Maximum lower than 70â nm and maximum External Quantum Efficiency between 7.2 % and 4.3 %. Overall, this shows that the 1,4-dihydropyrrolo[3,2-b]pyrrole moiety is promising for applications where luminescence is paramount, as in organic light-emitting devices.
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Columnar liquid crystals with very small molecular masses that form anisotropic glasses well above room temperature are obtained by mixed dissymmetric substitution of sym-triazine with ester-bearing phenyl and phenanthryl or tetrahelicenyl moieties. The combination of low molecular symmetry with configurational flexibility and short polar ester moieties stabilizes the mesophase over large temperature ranges and induces pronounced calorimetric glass transitions within the anisotropic fluid despite the smallness of the molecules. In contrast to more symmetrical homologs, no ester tails longer than ethyl are necessary to induce the liquid crystalline state, allowing for the near-absence of any insulating and weight-increasing alkyl periphery. Films drop-cast from solution show in all cases emission spectra that do not show significant change of fluorescence emission upon annealing, indicating that the columnar hexagonal mesoscopic order is obtained directly upon deposition from solution and is resistant to crystallization upon annealing.
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Triply phenanthryl- and tetrahelicenyl-substituted triazine-hexaalkyl esters with short alkyl chains show glass transitions conveniently above room temperature within the hexagonal columnar liquid crystalline state, resulting in a solid columnar order at room temperature. As the hexagonal columnar mesophase is easily aligned with the director perpendicular to a solid substrate, such glassy columnar liquid matrices are aimed at for the orientation of guest emitters, to obtain anisotropic emission. A condition for face-on alignment on substrates are attainable melting and clearing temperatures, which is achieved with the moderately nonplanar tetrahelicenyl derivatives in spite of their short alkyl periphery. An unusual phase transition between two columnar mesophases of same hexagonal symmetry, but very different long-distance regularity of the column lattice, is found in one phenanthryl homolog.
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Most organic room-temperature phosphorescence (RTP) emitters do not show their RTP in solution. Here, we incorporated sulfur-containing thiophene bridges between the donor and acceptor moieties in D3 A-type tristriazolotriazines (TTTs). The thiophene inclusion increased the spin-orbit coupling associated with the radiative T1 âS0 pathway, allowing RTP to be observed in solution for all compounds, likely assisted by protection of the emissive TTT-thiophene core from the environment by the bulky peripheral donors.
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According to the World Health Organization (WHO), cardiovascular diseases (CVDs) are the leading cause of mortality and morbidity worldwide. The development of electrochemical biosensors for CVD markers detection, such as cardiac troponin I (cTnI), becomes an important diagnostic strategy. Thus, a glassy carbon electrode (GCE) was modified with columnar liquid crystal (LCcol) and gold nanoparticles stabilized in polyallylamine hydrochloride (AuNPs-PAH), and the surface was employed to evaluate the interaction of the cTnI antibody (anti-cTnI) and cTnI for detection in blood plasma. Morphological and electrochemical investigations were used in the characterization and optimization of the materials used in the construction of the immunosensor. The specific interaction of cTnI with the surface of the immunosensor containing anti-cTnI was monitored indirectly using a redox probe. The formation of the immunocomplex caused the suppression of the analytical signal, which was observed due to the insulating characteristics of the protein. The cTnI-immunosensor interaction showed linear responses from 0.01 to 0.3 ng mL-1 and a low limit of detection (LOD) of 0.005 ng mL-1 for linear sweep voltammetry (LSV) and 0.01 ng mL-1 for electrochemical impedance spectroscopy (EIS), showing good diagnostic capacity for point-of-care applications.
Assuntos
Técnicas Biossensoriais , Cristais Líquidos , Nanopartículas Metálicas , Ouro/química , Troponina I , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Limite de DetecçãoRESUMO
Speeding up the phosphorescence channel in luminescent copper(I) complexes has been extremely challenging due to the copper atoms relatively low spin-orbit coupling constant compared to heavier metals such as iridium. Here, we report the synthesis and characterization of three mononuclear copper(I) complexes with diimines, triphenylphosphine, and iodide ligands to evaluate the effect of the copper-iodide (Cu-I) moiety into the phosphorescence decay pathway. Temperature-dependent photophysical studies revealed combined thermally activated delayed fluorescence and phosphorescence emission, with a phosphorescence decay rate of the order of 104 s-1. Density functional theory calculations indicate very high spin-orbit coupling matrix elements between the low-lying states of these complexes. Compared to the classical [Cu(phen)(POP)]+, our results demonstrate that Cu-I is a versatile moiety to speed up the phosphorescence decay pathway in about one order of magnitude, and it can be prepared by a simplified synthetic route with few synthetic steps. Furthermore, the SOC matrix elements and the phosphorescence decay rates of these complexes are comparable to those of extensively applied coordination complexes based on heavier metals, making them a promising alternative as active layers of organic light-emitting diodes.
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Herein, we describe a simple and efficient route to access aniline-derived diselenides and evaluate their antioxidant/GPx-mimetic properties. The diselenides were obtained in good yields via ipso-substitution/reduction from the readily available 2-nitroaromatic halides (Cl, Br, I). These diselenides present GPx-mimetic properties, showing better antioxidant activity than the standard GPx-mimetic compounds, ebselen and diphenyl diselenide. DFT analysis demonstrated that the electronic properties of the substituents determine the charge delocalization and the partial charge on selenium, which correlate with the catalytic performances. The amino group concurs in the stabilization of the selenolate intermediate through a hydrogen bond with the selenium.
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Resumen Pequeñas y aisladas poblaciones de borrego cimarrón (Ovis canadensis; especie sujeta a protección especial) son susceptibles a la depredación en hábitat simpátrico con venado bura. Entender las causas específicas de muerte y supervivencia es importante para el desarrollo de estrategias de conservación para el borrego cimarrón y otros ungulados que comparten el mismo hábitat, tal como el venado bura (Odocoileus hemionus). El objetivo de este estudio fue evaluar la tasa de depredación por puma (Puma concolor) en el borrego cimarrón y compararla con la del venado bura, para conocer la selección de presa del puma entre estas dos especies en un mismo hábitat, así como el impacto que podría tener en las poblaciones. Se plantea la hipótesis de que el puma como depredador oportunista no discrimina entre especies de ungulados simpátricos generando mayor impacto a la especie de menor densidad. Evaluamos la tasa de depredación por puma en 12 borregos cimarrones (10 hembras, 2 machos) y de 10 hembras adultas de venado bura con radio collares a través de micromorts y se comparó por medio una prueba de Wilcoxon, más la estimación de densidades de borrego y venados. Encontramos resultados similares en la causa específica de muerte por puma y supervivencia en ambas especies; 88 % (8/9) muertes debido a depredación por puma en borrego cimarrón con una tasa de supervivencia mensual promedio de 0.79 y una tasa mensual de depredación que va del rango 0.17-0.30. En venado bura la depredación debido a puma fue 83 % (5/6) con una tasa de supervivencia mensual promedio de 0.86 y una tasa de depredación por puma mensual en el rangos 0.10-0.25. Sin embargo, al comparar con la tasa de depredación por puma encontramos una diferencia significativa (Z = 1.826; df = 6; P = 0.05) siendo el borrego cimarrón la presa más selecta. En este estudio se concluye que el puma seleccionó a la presa de menor densidad (borrego cimarrón) y por ende la más impactada en un hábitat simpátrico con venado bura.(AU)
Abstract Small and isolated populations of bighorn sheep are vulnerable to predation by mountain lion in habitat sympatric with mule deer. Understanding the specific causes of death and survival is important for the development of conservation strategies for bighorn sheep and other ungulates that share the same habitat, such as mule deer. We evaluated and compared the rate of predation by puma in 12 bighorn sheep (10 females, two males) and 10 adult females of mule deer with radio collars through measure risk program (micromorts). The impact of predation in both populations of herbivores is evaluated through the estimation of densities of sheep and mule deer. 88 % (8/9) deaths by puma in bighorn sheep with an average monthly survival rate of 0.79 and predation rates due to puma range from 0.17 to 0.30. In mule deer predation due to puma was 83 % (5/6) with an average monthly survival rate of 0.86 and predation rates due to puma range from 0.10 to 0.25, however when comparing the mountain lion depredation rate we found a significant difference between species (Z = 1.826, df = 6, P = 0.05). The density in mule deer was 9x more that bighorn. The bighorn sheep being the prey most selected and the one most affected as the population with the lowest density.(AU)
Assuntos
Animais , Cervos , Ecossistema , Carneiro da Montanha , Puma , Taxa de Sobrevida , MéxicoRESUMO
Resumen La reintroducción de especies desaparecidas de mamíferos en sus hábitats históricos ha sido recientemente de gran interés. Desde 1967 se han realizado varios intentos de reintroducción del berrendo en México, ninguno ha sido exitoso. El objetivo de este estudio es proveer información que contribuya a evaluar el éxito de la liberación. El estudio se sustentó en el monitoreo de 100 individuos (70 hembras y 25 machos) capturados en Nuevo México E.U.A. y liberados en Maderas del Carmen, Coahuila, en dos etapas, el primer grupo de 45 individuos (20 hembras, 25 machos) liberado en la vertiente occidental de Maderas del Carmen en marzo 2009 y el segundo grupo en marzo 2010 con 55 individuos más (50 hembra, 5 machos). Se comparó la dispersión y mortalidad entre el método de liberación de adaptación vs liberación inmediata. La liberación con adaptación para esta especie dio un resultado altamente significativo (χ2= 2, α= 0.05, p= 0.0001). Los resultados de los métodos de liberación inmediata fueron de 23 % de mortalidad y 46 % de dispersión y los de la liberación de adaptación fueron de 4 y 13 % respectivamente. El método de liberación de adaptación es más benévolo que la liberación inmediata ayudando a reducir la dispersión y mortalidad por miopatía en translocaciones de berrendo. Por lo que el método de liberación con adaptación se recomienda utilizarlo en futuras liberaciones de berrendo ya que demuestra que más del 50 % de los berrendos procedentes de liberaciones inmediatas mueren por estrés de captura o se dispersan y con ello, se reducen las posibilidades de éxito.
Abstract The reintroduction of missing mammal species in former habitats has recently been of high interest. In Mexico, there have been several attempts to reintroduce Antilocapra since 1967, but until now none of the trials has been successful. Nowadays, different releasing methods have been practiced for mammal species, including soft and hard release ones. The aim of this study was to provide new information, and to evaluate the success of a recent release. The study was based on the monitoring of 100 individuals (70 females, 30 males) captured in New Mexico, USA, to be released in Maderas del Carmen, Coahuila, Mexico, in two different groups. The first group (fast release) of 45 specimens (20 females, 25 males) was released in the valley at the beginning of March 2009. The second one (soft release), with 55 individuals (50 female, 5 male), was released in March 2010. For both groups, we compared the mortality rate between dispersal and soft-release vs. hard-release methods. Our results showed that the release with adaptation gave highly significant results (χ2= 2, α= 0.05, p= 0.0001)). The comparison of mortality and dispersion among both methods was highly contrasting: with soft-release we obtained 4 % and 13 % of success, against 23 % and 46 %, respectively. Considering these results, we recommend the soft-release method to be used in future reintroduction attempts of Antilocapra, since more than 50 % of specimens from hard-releases died because of capture stress, or were dispersed, and thus reduced the reintroduction success chances. Rev. Biol. Trop. 65 (3): 1208-1214. Epub 2017 September 01.
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A nanostructured immunosensor based on the liquid crystal (E)-1-decyl-4-[(4-decyloxyphenyl)diazenyl]pyridinium bromide (Br-Py) and gold nanoparticles supported by the water-soluble hybrid material 3-n-propyl-4-picolinium silsesquioxane chloride (AuNP-Si4Pic(+)Cl(-)) was built for the detection of troponin T (cTnT), a cardiac marker for acute myocardial infarction (AMI). The functionalized nanostructured surface was used to bind anti-cTnT monoclonal antibodies through electrostatic interaction. The immunosensor (ab-cTnT/AuNP-Si4Pic(+)Cl(-)/Br-Py/GCE) surface was characterized by microscopy techniques. The electrochemical behavior of the immunosensor was studied by cyclic voltammetry and electrochemical impedance spectroscopy. A calibration curve was obtained by square-wave voltammetry. The immnunosensor provided a limit of detection of 0.076 ng mL(-1) and a linear range between 0.1 and 0.9 ng mL(-1) (appropriate for AMI diagnosis).
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Técnicas Biossensoriais/métodos , Ouro/química , Imunoensaio/métodos , Cristais Líquidos/química , Nanopartículas Metálicas/química , Compostos de Organossilício/química , Troponina T/análise , Calibragem , Eletroquímica , Humanos , Compostos de Piridínio/química , Reprodutibilidade dos TestesRESUMO
The incorporation of dyes in liquid crystal matrices has been exploited to produce enhanced displays, but it can also be used to probe ordering in liquid crystals and to assess intermolecular interactions and dye aggregation. In this study, we investigated polarized absorption and emission of the luminescent dyes 4,7-bis(2-(4-(decyloxy)phenyl)ethynyl)-[2,1,3]-benzothiadiazole (1A) and 4,7-bis{2-[4-(4-decylpiperazin-1-yl)phenyl]ethynyl}-[2,1,3]-benzothiadiazole (5A) in the E7® liquid crystal. The electronic structures of both 1A and 5A dyes were affected by the matrix and by the analysis of the line shape of emission we could determine that the dyes form J aggregates. This achievement is significant because obtaining this type of information for small molecules requires ordered matrices, which is difficult to obtain for these dyes. Using emission ellipsometry we were able to determine the ordering of the E7 molecules, but this was possible only with the larger 5A dye. The smaller 1A was not entirely ordered in the E7 matrix and this calls for caution in other types of work where dopants are used as probes to infer the properties of the matrix. The emission ellipsometry data for the dyes allowed us to detect the enhanced birefringence in the matrix, thus confirming the theoretical prediction.
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Columnar liquid crystals are composed of disk-shaped aromatic molecules surrounded by flexible side chains, where molecules self-assemble in columns and thereby form large surface-oriented domains. These systems are known for their good charge and exciton transport along the columns, with mobilities approaching those of aromatic single crystals. Such semiconducting materials are promising for devices applications, since the output efficiency can be tuned by properly aligning columns. In the work presented here, the synthesis and characterization of a new Zn-phthalocyanine (ZnPc) is described which exhibits remarkable properties, such as hexagonal columnar order, achieved by cooling down from the isotropic phase to room temperature. Such order was confirmed by optical microscopy and X-ray diffraction experiments. Diodes were constructed using spin-coated films, and the conductive properties were investigated by current versus voltage analysis, where mobilities of 10(-3) and 10(-2) cm(2)/(V s) were obtained for the nonannealed and annealed films, respectively.
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Five discotic molecules comprising a tris[1,2,4]triazolo[1,3,5] triazine core were designed and synthesized to obtain luminescent and charge-transporting columnar liquid crystalline materials. With the exception of one compound containing terminal hydroxyl groups all compounds presented a wide thermal range and stable columnar liquid crystalline phase, characterized by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction (XRD) techniques. The phase formation appeared to be associated to some extent with interdigitation of the alkoxy and benzylalkoxy portion, as suggested by the XRD results. All compounds have a strong blue luminescence in solution and solid phase. At the temperature at which the compounds enter in the mesophase the luminescence decreases significantly. This result suggests that entrance into the Col(h) phase is accompanied by a better π-stacking of the peripheral phenyl rings compared to the solid phase, consistent with the intramolecular distances (3.5 Å) observed in the XRD analysis. These compounds based on tristriazolotriazine are quite robust with good optical and thermal properties for application as solid state emitters, and we anticipate that they may provide an interesting alternative to other discotic molecules based on N-heterocycles, which generally present a high-temperature Col(h) phase.
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A new iron(ii) complex was synthesized and its photonuclease activity against plasmid DNA was evaluated. After kinetic experiments a k(cat) of 18.86 +/- 2.9 h(-1) was obtained, one of the highest nuclease activities of synthetic metallonucleases, selectively activated by 365 nm UV light.
Assuntos
DNA/efeitos dos fármacos , Compostos Ferrosos/farmacologia , Oxigênio/química , Cristalografia por Raios X , DNA/química , Clivagem do DNA , Desoxirribonucleases/química , Desoxirribonucleases/metabolismo , Compostos Ferrosos/síntese química , Compostos Ferrosos/química , Ligantes , Modelos Moleculares , Estrutura Molecular , Fotólise , Plasmídeos/química , Raios UltravioletaRESUMO
In the structure of the title compound, C(21)H(30)BrNOS, an important inter-mediate for the preparation of liquid crystal compounds, the saturated C(12) chain shows a linear conformation while the benzene and thia-zole rings are essentially coplanar [dihedral angle = 4.5â (4)°]. The crystal packing shows no significant inter-molecular inter-actions.
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The crystal structure of the title compound, C(12)H(9)F(3)N(2)O(2), contains two independent mol-ecules in the asymmetric unit. The mol-ecules are chemically identical but exhibit a significant difference in the dihedral angles between the mean planes of the phenyl and pyrazole rings, with values of of 11.62â (13) and 18.17â (11)°. Moreover, the trifluoro-methyl group in one of the mol-ecules shows rotational disorder of the F atoms, with site occupancy factors of 0.929â (6) and 0.071â (6). The hydroxyl group in each of the mol-ecules shows a strong intra-molecular hydrogen bond with the carbonyl O atom, forming a six-membered ring and forcing the formyl group and pyrazole ring to be coplanarshowing C-C-C-O torsion angles of ?0.3(5)o and 0.°. Weak inter-molecular C-Hâ¯O and C-Hâ¯F inter-actions contribute to the stabilization of the crystal packing.
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The title compound, C(10)H(7)F(3)N(2)O, is an analogue of pyrazolone derivatives with potential analgesic and anti-inflammatory properties. Its mol-ecular structure consists of phenyl and pyrazol-3(2H)-one units with a dihedral angle between the mean planes of the rings of 33.0â (1)°. The crystal structure is stabilized by an inter-molecular hydrogen bond between the N-H group and the carbonyl O atom of the pyrazol-3(2H)-one ring which links the mol-ecules into supra-molecular C(5) chains along [001] and by weak π-π stacking inter-actions between the phenyl rings [centroid-centroid distance = 3.881â (2)â Å]. The F atoms are disordered over two positions with refined site occupancies of 0.768(11) and 0.232(11).
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The synthesis and structural, thermal, optical and theoretical characterization of new tris[1,2,4]triazolo[1,3,5]triazines were performed to support their application as liquid crystals and advanced materials.