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1.
Intensive Care Med Exp ; 12(1): 69, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133363

RESUMEN

BACKGROUND: Critical care management heavily relies on accurate cardiac output (CO) measurement. Echocardiography has been a mainstay in non-invasive cardiac monitoring; however, its comparability to invasive methods warrants further exploration. Recent studies have suggested the potential of carotid Doppler measurements as a promising approach to estimate CO. Despite this potential, the literature presents mixed outcomes regarding its reliability and accuracy. This study aims to evaluate the correlation and concordance between carotid Doppler ultrasonography and invasive hemodynamic monitoring in estimating CO in critically ill patients. Furthermore, it assesses the concordance and correlation between echocardiography CO and the standard invasive CO measurements. METHODS: This concordance study involved critically ill adults requiring invasive CO measurement. Patients with arrhythmias, severe valvulopathy, pregnancy, and poor acoustic window were excluded. Statistical analyses comprised univariate analysis, Wilcoxon signed-rank test, Spearman correlation, and intraclass correlation coefficient. Ethical approval was granted by the institution's ethics committee. RESULTS: A total of 49 critically ill patients were included, predominantly male (63.27%), with a median age of 57 years. Diagnoses included subarachnoid hemorrhage (53.06%) and heart failure (8.16%). Mean cardiac index was 3.36 ± 0.81 L/min/m2 and mean cardiac output was 5.98 ± 1.47 L/min. Spearman correlation coefficient between echocardiography and invasive CO measurements was 0.58 (p-value = p < 0.001), with an ICC of 0.59 for CO and 0.52 for cardiac index. Carotid measurements displayed no significant correlation with invasive CO. CONCLUSION: There is a moderate correlation and concordance between echocardiography and invasive CO measurements. There is no significant correlation between carotid variables and invasive CO, underscoring the necessity for cautious interpretation and application, particularly in patients with distinctive cerebral blood flow dynamics.

2.
Artículo en Inglés | MEDLINE | ID: mdl-36981880

RESUMEN

Accessibility to housing is crucial for people with disabilities as it provides them with equal opportunities and allows them to live independently. A systematic literature review has been conducted to understand the current research on accessibility in housing for people with disabilities in Latin America. The study analysed 56 papers and used co-word analysis to identify common themes and topics within the documents. The results of the analysis showed that Brazil (61%) is the country with the most research on the subject, physical disability, at 36%, is the impairment most analysed, and interventions or analysis for the older people (45%) in their homes is the most researched type of population. The co-word analysis revealed that topics such as policy, regulations, the use of technologies, ergonomics interventions, and architectural criteria or barriers to the daily life of disabled people were frequently discussed in the papers. Although this work shows a substantial and growing increase in research on housing for people with disabilities in Latin America, it also demonstrates the importance of increasing research on other types of impairment, such as visual and cognitive-intellectual disabilities, and including children, caregivers, or even young adults.


Asunto(s)
Personas con Discapacidad , Discapacidad Intelectual , Niño , Adulto Joven , Humanos , Anciano , Vivienda , América Latina , Políticas
3.
J Phys Chem A ; 127(10): 2407-2414, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36876889

RESUMEN

Identifying chemical compounds is essential in several areas of science and engineering. Laser-based techniques are promising for autonomous compound detection because the optical response of materials encodes enough electronic and vibrational information for remote chemical identification. This has been exploited using the fingerprint region of infrared absorption spectra, which involves a dense set of absorption peaks that are unique to individual molecules, thus facilitating chemical identification. However, optical identification using visible light has not been realized. Using decades of experimental refractive index data in the scientific literature of pure organic compounds and polymers over a broad range of frequencies from the ultraviolet to the far-infrared, we develop a machine learning classifier that can accurately identify organic species based on a single-wavelength dispersive measurement in the visible spectral region, away from absorption resonances. The optical classifier proposed here could be applied to autonomous material identification protocols and applications.

4.
Pensar mov ; 20(2)dic. 2022.
Artículo en Español | LILACS, SaludCR | ID: biblio-1422230

RESUMEN

Cornejo, M. I., Henríquez, M., Herrera, F., Muñoz, F., Bernardes, N., Auricchio, J. R., y Castelli-Correia de Campos, L. F. (2022). Percepción de la calidad de vida en para- deportistas y no deportistas chilenos con lesión cerebral. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20 (2), 1-18. La calidad de vida (CV) y la actividad física son aspectos relevantes en la salud de la población, y esta última con un impacto positivo en las personas con discapacidad. Debido a esto, los objetivos de este estudio fueron comparar las características e identificar la asociación entre los dominios de la percepción de la CV entre un grupo de personas con lesión cerebral que practican fútbol, para-deportistas (PD) y personas con lesión cerebral no para-deportistas (NPD), además determinar si existen diferencias en la percepción de la CV según las diferentes clases deportivas (FT1, FT2 y FT3). El estudio se desarrolló en Chile, donde se aplicó el cuestionario WHOQOL-BREF para determinar la CV de los participantes. Los resultados identificaron una relación positiva y significativa entre los distintos dominios de la CV (p < .001, r = .44 - .67). Además, se observó una mejor percepción de la CV en los PD (p < .001, TE = 1.18, grande) en comparación con lo reportado por el grupo NPD. Por otro lado, no se obtuvieron diferencias significativas entre los dominios para las diferentes clases deportivas en el grupo PD. Estos datos refuerzan la idea de que la práctica deportiva influye en la participación social y en la percepción de la CV en PD con lesión cerebral. El desarrollo conjunto de los factores asociados entre la salud y el bienestar socioemocional podrían colaborar con la consolidación de la práctica deportiva y de actividad física, los cuales, a su vez son beneficiosos para las personas con discapacidad tal como lo plantean los objetivos del desarrollo sostenible en su agenda de trabajo provista al año 2030.


Cornejo, M. I., Henríquez, M., Herrera, F., Muñoz, F., Bernardes, N., Auricchio, J. R., y Castelli-Correia de Campos, L. F. (2022). Perception of quality of life in chilean para-athletes and non-athletes with brain injury. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20 (2), 1-16. Quality of life (QOL) and physical activity are relevant aspects in the health of the population, and the latter has a positive impact on people with disabilities. For this reason, the objectives of this study were to compare the characteristics and identify the association between the domains of QOL perception between a group of people with brain injury who practice soccer, para-athletes (PD) and non-para-athletes with brain injury (NPD), as well as to determine if there are differences in the perception of QOL according to the different sports classes (FT1, FT2 and FT3). The study was carried out in Chile, where the WHOQOL-BREF questionnaire was applied to determine the QOL of participants. The results identified a positive and significant relationship between the different domains of QOL (p < .001, r = .44 - .67). In addition, a better perception of QoL was observed in the PDs (p < .001, TE = 1.18, large) compared to that reported by the NPD group. On the other hand, no significant differences between domains were obtained for the different sport classes in the PD group. These data reinforce the idea that sport practice influences social participation and perception of QoL in PD with brain injury. The joint development of the factors associated between health and socioemotional well-being could collaborate in the consolidation of sports practice and physical activity, which, in turn, are beneficial for people with disabilities, as proposed by the Sustainable Development Goals in their work agenda foreseen for the year 2030.


Cornejo, M. I., Henríquez, M., Herrera, F., Muñoz, F., Bernardes, N., Auricchio, J. R., y Castelli-Correia de Campos, L. F. (2022). Percepção da qualidade de vida em paratletas e não-atletas chilenos com lesões cerebrais. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 20 (2), 1-16. Qualidade de vida (QV) e atividade física são aspectos relevantes da saúde da população, tendo esta última um impacto positivo sobre as pessoas com deficiências. Portanto, os objetivos deste estudo foram comparar as características e identificar a associação entre os domínios da percepção de QV entre um grupo de pessoas com lesões cerebrais que praticam futebol, paratletas (P) e pessoas com lesões cerebrais não paratletas (NP), e determinar se existem diferenças na percepção de QV de acordo com as diferentes classes esportivas (FT1, FT2 e FT3). O estudo foi realizado no Chile, onde o questionário WHOQOL-BREF foi utilizado para determinar o QV dos participantes. Os resultados identificaram uma relação positiva e significativa entre os diferentes domínios da QV (p < 0,001, r = 0,44 - 0,67). Além disso, uma melhor percepção de QV foi observada nos Ps (p < 0,001, TE = 1,18, grande) em comparação com a relatada pelo grupo NP. Por outro lado, não foram obtidas diferenças significativas entre os domínios para as diferentes classes esportivas do grupo P. Estes dados reforçam a ideia de que a prática esportiva influencia a participação social e a percepção da QV nos P com lesão cerebral. O desenvolvimento conjunto de fatores associados à saúde e ao bem-estar socioemocional poderia contribuir para a consolidação da prática do esporte e da atividade física, que, por sua vez, são benéficos para as pessoas com deficiência, conforme estabelecido nas Metas de Desenvolvimento Sustentável em sua agenda para 2030.


Asunto(s)
Humanos , Masculino , Adulto , Calidad de Vida , Fútbol , Parálisis Cerebral , Chile , Discapacidad Intelectual
5.
J Chem Phys ; 157(19): 194104, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36414439

RESUMEN

Modeling the non-equilibrium dissipative dynamics of strongly interacting quantized degrees of freedom is a fundamental problem in several branches of physics and chemistry. We implement a quantum state trajectory scheme for solving Lindblad quantum master equations that describe coherent and dissipative processes for a set of strongly coupled quantized oscillators. The scheme involves a sequence of stochastic quantum jumps with transition probabilities determined by the system state and the system-reservoir dynamics. Between consecutive jumps, the wave function is propagated in a coordinate space using the multi-configuration time-dependent Hartree method. We compare this hybrid propagation methodology with exact Liouville space solutions for physical systems of interest in cavity quantum electrodynamics, demonstrating accurate results for experimentally relevant observables using a tractable number of quantum trajectories. We show the potential for solving the dissipative dynamics of finite size arrays of strongly interacting quantized oscillators with high excitation densities, a scenario that is challenging for conventional density matrix propagators due to the large dimensionality of the underlying Hilbert space.

6.
ACS Omega ; 7(28): 24432-24437, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35874204

RESUMEN

Metal-organic frameworks (MOFs) have emerged as promising tailor-designed materials for developing next-generation solid-state devices with applications in linear and nonlinear coherent optics. However, the implementation of functional devices is challenged by the notoriously difficult process of growing large MOF single crystals of high optical quality. By controlling the solvothermal synthesis conditions, we succeeded in producing large individual single crystals of the noncentrosymmetric MOF Zn(3-ptz)2 (MIRO-101) with a deformed octahedron habit and surface areas of up to 37 mm2. We measured the UV-vis absorption spectrum of individual Zn(3-ptz)2 single crystals across different lateral incidence planes. Millimeter-sized single crystals have a band gap of E g = 3.32 eV and exhibit anisotropic absorption in the band-edge region near 350 nm, whereas polycrystalline samples are fully transparent in the same frequency range. Using solid-state density functional theory (DFT), the observed size dependence in the optical anisotropy is correlated with the preferred orientation adopted by pyridyl groups under conditions of slow crystal self-assembly. Our work thus paves the way for the development of optical polarization switches based on metal-organic frameworks.

7.
Materials (Basel) ; 15(11)2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35683252

RESUMEN

This article focuses on agar biopolymer films that offer promise for developing biodegradable packaging, an important solution for reducing plastics pollution. At present there is a lack of data on the mechanical performance of agar biopolymer films using a simple plasticizer. This study takes a Design of Experiments approach to analyze how agar-glycerin biopolymer films perform across a range of ingredients concentrations in terms of their strength, elasticity, and ductility. Our results demonstrate that by systematically varying the quantity of agar and glycerin, tensile properties can be achieved that are comparable to agar-based materials with more complex formulations. Not only does our study significantly broaden the amount of data available on the range of mechanical performance that can be achieved with simple agar biopolymer films, but the data can also be used to guide further optimization efforts that start with a basic formulation that performs well on certain property dimensions. We also find that select formulations have similar tensile properties to thermoplastic starch (TPS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP), indicating potential suitability for select packaging applications. We use our experimental dataset to train a neural network regression model that predicts the Young's modulus, ultimate tensile strength, and elongation at break of agar biopolymer films given their composition. Our findings support the development of further data-driven design and fabrication workflows.

8.
J Chem Phys ; 156(12): 124110, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35364879

RESUMEN

Nanoscale infrared (IR) resonators with sub-diffraction limited mode volumes and open geometries have emerged as new platforms for implementing cavity quantum electrodynamics at room temperature. The use of IR nanoantennas and tip nanoprobes to study strong light-matter coupling of molecular vibrations with the vacuum field can be exploited for IR quantum control with nanometer spatial and femtosecond temporal resolution. In order to advance the development of molecule-based quantum nanophotonics in the mid-IR, we propose a generally applicable semi-empirical methodology based on quantum optics to describe light-matter interaction in systems driven by mid-IR femtosecond laser pulses. The theory is shown to reproduce recent experiments on the acceleration of the vibrational relaxation rate in infrared nanostructures. It also provides physical insights on the implementation of coherent phase rotations of the near-field using broadband nanotips. We then apply the quantum framework to develop general tip-design rules for the experimental manipulation of vibrational strong coupling and Fano interference effects in open infrared resonators. We finally propose the possibility of transferring the natural anharmonicity of molecular vibrational levels to the resonator near-field in the weak coupling regime to implement intensity-dependent phase shifts of the coupled system response with strong pulses and develop a vibrational chirping model to understand the effect. The semi-empirical quantum theory is equivalent to first-principles techniques based on Maxwell's equations, but its lower computational cost suggests its use as a rapid design tool for the development of strongly coupled infrared nanophotonic hardware for applications ranging from quantum control of materials to quantum information processing.

9.
J Chem Phys ; 156(11): 114702, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35317564

RESUMEN

We propose to use molecular picocavity ensembles as macroscopic coherent nonlinear optical devices enabled by nanoscale strong coupling. For a generic picocavity model that includes molecular and photonic disorder, we derive theoretical performance bounds for coherent cross-phase modulation signals using weak classical fields of different frequencies. We show that strong coupling of the picocavity vacua with a specific vibronic sideband in the molecular emission spectrum results in a significant variation of the effective refractive index of the metamaterial relative to a molecule-free scenario due to a vacuum-induced Autler-Townes effect. For a realistic molecular disorder model, we demonstrate that cross-phase modulation of optical fields as weak as 10 kW/cm2 is feasible using dilute ensembles of molecular picocavities at room temperature, provided that the confined vacuum is not resonantly driven by the external probe field. Our work paves the way for the development of plasmonic metamaterials that exploit strong coupling for optical state preparation and quantum control.

10.
ACS Omega ; 6(27): 17289-17298, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34278115

RESUMEN

The solvothermal synthesis of metal-organic frameworks (MOFs) often proceeds through competing crystallization pathways, and only partial control over the crystal nucleation and growth rates is possible. It challenges the use of MOFs as functional devices in free-space optics, where bulk single crystals of millimeter dimensions and high optical quality are needed. We develop a synthetic protocol to control the solvothermal growth of the MOF [Zn(3-ptz)2] n (MIRO-101), to obtain large single crystals with projected surface areas of up to 25 mm2 in 24 h, in a single reaction with in situ ligand formation. No additional cooling and growth steps are necessary. We propose a viable reaction mechanism for the formation of MIRO-101 crystals under acidic conditions, by isolating intermediate crystal structures that directly connect with the target MOF and reversibly interconverting between them. We also study the nucleation and growth kinetics of MIRO-101 using ex situ crystal image analysis. The synthesis parameters that control the size and morphology of our target MOF crystal are discussed. Our work deepens our understanding of MOF growth processes in solution and demonstrates the possibility of building MOF-based devices for future applications in optics.

11.
Am J Case Rep ; 22: e928420, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-34111056

RESUMEN

BACKGROUND Pesticides are commonly used in the agricultural industry. Overdose can be lethal due to its effects generating closure of the voltage-gated sodium channels in the axonal membranes. Most case reports of toxicity refer to skin exposure and there are very few that refer to effects due to its oral intake. CASE REPORT We report the case of an elderly woman with Alzheimer disease who accidentally swallowed 50 g of Lambda Cyhalothrin (GOLPE 5 M E®), a pyrethroid of medium toxicity containing a cyano group. It severely harmed the woman's health, causing severe central nervous system depression and refractory vasodilated shock requiring the use of vasopressors. Its management was challenging, requiring orotracheal intubation, vasopressors, and admission to the Intensive Care Unit (ICU). The emergency care team decided to use intravenous lipid emulsion, which clearly helped with the recovery and successful discharge of the patient. CONCLUSIONS The use of intravenous lipid emulsion for the treatment of pyrethroid poisoning can lead to successful outcomes, as described in this case report.


Asunto(s)
Enfermedad de Alzheimer , Sobredosis de Droga , Plaguicidas , Piretrinas , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/tratamiento farmacológico , Sobredosis de Droga/tratamiento farmacológico , Emulsiones Grasas Intravenosas/uso terapéutico , Femenino , Humanos , Piretrinas/uso terapéutico
12.
J Chem Phys ; 152(23): 234111, 2020 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-32571050

RESUMEN

Vibrational strong coupling has emerged as a promising route for manipulating the reactivity of molecules inside infrared cavities. We develop a full-quantum methodology to study the unitary dynamics of a single anharmonic vibrational mode interacting with a quantized infrared cavity field. By comparing multi-configurational time-dependent Hartree simulations for an intracavity Morse oscillator with an equivalent formulation of the problem in Hilbert space, we describe for the first time the essential role of permanent dipole moments in the femtosecond dynamics of vibrational polariton wavepackets. We classify molecules into three general families according to the shape of their electric dipole function de(q) along the vibrational mode coordinate q. For polar species with a positive slope of the dipole function at equilibrium, an initial diabatic light-matter product state without vibrational or cavity excitations evolves into a polariton wavepacket with a large number of intracavity photons for interaction strengths at the conventional onset of ultrastrong coupling. This buildup of the cavity photon amplitude is accompanied by an effective lengthening of the vibrational mode that is comparable with a laser-induced vibrational excitation in free space. In contrast, polar molecules with a negative slope of the dipole function experience an effective mode shortening, under equivalent coupling conditions. We validate our predictions using realistic ab initio ground state potentials and dipole functions for HF and CO2 molecules. We also propose a non-adiabatic state preparation scheme to generate vibrational polaritons with molecules near infrared nanoantennas for the spontaneous radiation of infrared quantum light.

13.
J Chem Phys ; 152(10): 100902, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32171209

RESUMEN

This is a tutorial-style introduction to the field of molecular polaritons. We describe the basic physical principles and consequences of strong light-matter coupling common to molecular ensembles embedded in UV-visible or infrared cavities. Using a microscopic quantum electrodynamics formulation, we discuss the competition between the collective cooperative dipolar response of a molecular ensemble and local dynamical processes that molecules typically undergo, including chemical reactions. We highlight some of the observable consequences of this competition between local and collective effects in linear transmission spectroscopy, including the formal equivalence between quantum mechanical theory and the classical transfer matrix method, under specific conditions of molecular density and indistinguishability. We also overview recent experimental and theoretical developments on strong and ultrastrong coupling with electronic and vibrational transitions, with a special focus on cavity-modified chemistry and infrared spectroscopy under vibrational strong coupling. We finally suggest several opportunities for further studies that may lead to novel applications in chemical and electromagnetic sensing, energy conversion, optoelectronics, quantum control, and quantum technology.

14.
J Chem Phys ; 151(14): 144116, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31615252

RESUMEN

We propose a cavity QED approach to describe light-matter interaction of an infrared cavity field with an anharmonic vibration of a single nonpolar molecule. Starting from a generic Morse oscillator potential with quantized nuclear motion, we derive a multilevel quantum Rabi model to study vibrational polaritons beyond the rotating-wave approximation. We analyze the spectrum of vibrational polaritons in detail and compare it with available experiments. For high excitation energies, the system exhibits a dense manifold of polariton level crossings and avoided crossings as the light-matter coupling strength and cavity frequency are tuned. We also analyze polariton eigenstates in nuclear coordinate space. We show that the bond length of a vibrational polariton at a given energy is never greater than the bond length of a Morse oscillator with the same energy. This type of polariton bond strengthening occurs at the expense of the creation of virtual infrared cavity photons and may have implications in chemical reactivity of polariton states.

15.
ACS Omega ; 4(11): 14398-14403, 2019 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-31528792

RESUMEN

We describe the structure and properties of [Zn(C6H4N5)N3] n , a new nonporous three-dimensional high-energy metal-organic framework (HE-MOF) with enhanced thermal stability. The compound is synthesized by the hydrothermal method with in situ ligand formation under controlled pH and characterized using single-crystal X-ray diffraction, elemental analysis, and Fourier transform infrared. The measured detonation temperature (T det = 345 °C) and heat of detonation (ΔH det = -0.380 kcal/g) compare well with commercial explosives and other nitrogen-rich HE-MOFs. The velocity and pressure of denotation are 5.96 km/s and 9.56 GPa, respectively. Differential scanning calorimetry analysis shows that the denotation of [Zn(C6H4N5)N3] n occurs via a complex temperature-dependent mechanism.

16.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 6): 867-871, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31391984

RESUMEN

The title compound, [Ni(C10H8N2)3](C9H5N4O)2·2H2O, crystallizes as a racemic mixture in the monoclinic space group C2/c. In the crystal, the 1,1,3,3-tetracyano-2-ethoxypropenide anions and the water molecules are linked by O-H⋯N hydrogen bonds, forming chains running along the [010] direction. The bpy ligands of the cation are linked to the chain via C-H⋯π(cation) inter-actions involving the CH3 group. The inter-molecular inter-actions were investigated by Hirshfeld surface analysis and two-dimensional fingerprint plots.

17.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 9): 1231-1234, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30225106

RESUMEN

Hexa-aqua-zinc(II) dinitrate 5-(pyridinium-3-yl)tetra-zol-1-ide, [Zn(H2O)6](NO3)2·2C6H5N5, crystallizes in the space group P . The asymmetric unit contains one zwitterionic 5-(pyridinium-3-yl)tetra-zol-1-ide mol-ecule, one NO3- anion and one half of a [Zn(H2O)6]2+ cation ( symmetry). The pyridinium and tetra-zolide rings in the zwitterion are nearly coplanar, with a dihedral angle of 5.4 (2)°. Several O-H⋯N and N-H⋯O hydrogen-bonding inter-actions exist between the [Zn(H2O)6]2+ cation and the N atoms of the tetra-zolide ring, and between the nitrate anions and the N-H groups of the pyridinium ring, respectively, giving rise to a three-dimensional network. The 5-(pyridinium-3-yl)tetra-zol-1-ide mol-ecules show parallel-displaced π-π stacking inter-actions; the centroid-centroid distance between adjacent tetra-zolide rings is 3.6298 (6) Šand that between the pyridinium and tetra-zolide rings is 3.6120 (5) Å.

18.
ACS Omega ; 3(1): 801-807, 2018 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31457930

RESUMEN

We report the synthesis and structural diversity of Zn(II) metal-organic framework (MOF) with in situ formation of tetrazole ligand 3-ptz [3-ptz = 5-(3-pyridyl)tetrazolate] as a function pH. By varying the initial reaction pH, we obtain high-quality crystals of the noncentrosymmetric three-dimensional MOF Zn(3-ptz)2 , mixed phases involving the zinc-aqua complex [Zn(H2O)4(3-ptz)2]·4H2O, and two-dimensional MOF crystals Zn(OH)(3-ptz) with a tunable microrod morphology, keeping reaction time, temperature, and metal-ligand molar ratio constant. Structures are characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-vis spectroscopy. We discuss the observed structural diversity in terms of the relative abundance of hydroxo-zinc species in solution for different values of pH.

19.
Phys Rev Lett ; 118(22): 223601, 2017 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-28621976

RESUMEN

Organic microcavities are photonic nanostructures that strongly confine the electromagnetic field, allowing exotic quantum regimes of light-matter interaction with disordered organic semiconductors. The unambiguous interpretation of the spectra of organic microcavities has been a long-standing challenge due to several competing effects involving electrons, vibrations, and cavity photons. Here we present a theoretical framework that is able to describe the main spectroscopic features of organic microcavities consistently. We introduce a class of light-matter excitations called dark vibronic polaritons, which strongly emit but only weakly absorb light in the same frequency region of the bare electronic transition. A successful comparison with experimental data demonstrates the applicability of our theory. The proposed microscopic understanding of organic microcavities paves the way for the development of optoelectronic devices enhanced by quantum optics.

20.
Acta méd. colomb ; 42(2): 140-143, abr.-jun. 2017. graf
Artículo en Español | LILACS, COLNAL | ID: biblio-886354

RESUMEN

Resumen La porfiria intermitente aguda (PIA) es una enfermedad poco frecuente, considerada huérfana, que se caracteriza por crisis neuroviscerales, el dolor abdominal siendo su síntoma más común, acompañado en muchos casos, de síntomas inespecíficos, haciendo difícil su diagnóstico temprano. El retraso en el diagnóstico y tratamiento de esta entidad puede resultar catastrófico o incluso fatal, provocando daño neurológico a largo plazo o permanente. Reportamos el caso de un adulto joven que consulta en varias ocasiones por dolor abdominal inespecífico y 24 horas después de la admisión desarrolla inestabilidad autonómica simpática con cifras tensionales elevadas y taquicardia. Posteriormente debilidad muscular que evoluciona hasta cuadriplejia e hiponatremia con criterios para secreción inadecuada de hormona antidiurética (SIADH). Estos datos, junto con coloración rojiza en orina, llevan al diagnóstico de porfiria. Presentamos las características clínicas y bioquímicas enfatizando la importancia de incluir la porfiria dentro de los diagnósticos diferenciales de dolor abdominal y disautonomia de causa indeterminada. (Acta Med Colomb 2017; 42: 140-143).


Abstract Acute intermittent porphyria (AIP) is an infrequent and considered orphan disease, characterized by neurovisceral crisis, being abdominal pain the most common symptom, accompanied in many cases by non-specific symptoms, making early diagnosis difficult. The delay in the diagnosis and treatment of this entity can be catastrophic or even fatal, causing long-term or permanent neurological damage. The case of a young adult who attends medical consultation several times for non-specific abdominal pain and 24 hours after admission develops sympathetic autonomic instability with elevated blood pressure and tachycardia is presented. He subsequently presents muscular weakness that evolves to quadriplegia and hyponatremia with criteria for inadequate secretion of antidiuretic hormone (SIADH). These data together with reddish urine staining lead to the diagnosis of porphyria. The clinical and biochemical characteristics emphasizing the importance of including porphyria within the differential diagnoses of abdominal pain and dysautonomia of indeterminate cause are presented. (Acta Med Colomb 2017; 42: 140-143).


Asunto(s)
Humanos , Masculino , Adulto , Porfirias , Cuadriplejía , Porfiria Intermitente Aguda , Disautonomías Primarias , Síndrome de Secreción Inadecuada de ADH
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