Variational Quantum Simulators Based on Waveguide QED.

Waveguide QED simulators are analog quantum simulators made by quantum emitters interacting with one-dimensional photonic band gap materials. One of their remarkable features is that they can be used to engineer tunable-range emitter interactions. Here, we demonstrate how these interactions can be a resource to develop more efficient variational quantum algorithms for certain problems. In particular, we illustrate their power in creating wave function Ansätze that capture accurately the ground state of quantum critical spin models (XXZ and Ising) with fewer gates and optimization parameters than other variational Ansätze based on nearest-neighbor or infinite-range entangling gates. Finally, we study the potential advantages of these waveguide Ansätze in the presence of noise. Overall, these results evidence the potential of using the interaction range as a variational parameter and place waveguide QED simulators as a promising platform for variational quantum algorithms.

Medida de la precariedad laboral en Centroamérica: propiedades psicométricas en base a la II Encuesta Centroamericana de Condiciones de Trabajo y Salud / Precarious employment Measurement in Central America: psychometric properties based on the II Central American Survey of Working Conditions and Health

Objetivo: Establecer las propiedades psicométricas de una medida de Precariedad Laboral (PL) en seis países centroamericanos de habla española (Costa Rica, El Salvador, Guate-mala, Honduras, Nicaragua y Panamá) mediante un conjunto de ítems incluidos en la II Encuesta Centroamericana de Condiciones de Trabajo y Salud (II ECCTS) de 2018 que se correspondían con ítems de la Escala de Precariedad Laboral (EPRES).Método: A partir de una muestra de 3.782 personas asalariadas de 18 años o más, forma-les e informales, en la II ECCTS, se construyó una medida de PL de 10 ítems representan-do tres dimensiones (temporalidad, derechos y ejercicio de derechos), además del salario como variable observada.Resultados: La muestra estuvo compuesta en su mayoría por hombres, con contrato per-manente, con antigüedad laboral de entre 2 a 5 años, un salario entre 301 a 500 dólares, que reportaban tener derechos laborales y ejercerlos. El Análisis Factorial Confirmatorio corroboró la estructura de la escala (RMSEA 0,07; SRMR = 0,05; CFI = 0,96 y TLI = 0,94). Se observó una alta aceptabilidad de medida de PL y los coeficientes de Alpha de Cronbach de las dimensiones fueron >0,59 excepto para temporalidad (0,30). La confiabilidad de la esca-la fue de 0,68, demostró ser sensible y los patrones de PL en mujeres, jóvenes, temporales y países con menores ingresos fueron los esperados.Conclusiones: La medida de PL construida a partir de ítems disponibles de la escala EPRES en el cuestionario de la II ECCTS evidencia propiedades psicométricas aceptables para aproximarnos a la cuantificación epidemiológica de la PL en Centroamérica (AU)

Objective: To examine the psychometric properties of a measure of Employment Precari-ousness (EP) in six Spanish-speaking Central American countries (Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama) consisting of items from in the Employ-ment Precariousness Scale (EPRES) included in the 2018 II Central American Survey of Working Conditions and Health (II ECCTS).Methods: The study sample consisted of 3782 salaried persons, age 18 years and older, both formal and informal, who participated in the II ECCTS. We constructed a 10-item EP measure was constructed, grouped into three dimensions (temporality, labor rights, and exercise of these rights), in addition to salary as an observed variable.Results: The sample was composed mostly of men, with a permanent contract, a work-ing age of between 2 to 5 years, a salary between $301 and $500, who have labor rights and who exercise them. The Confirmatory Factor Analysis corroborated the structure of the scale (RMSEA 0.07, SRMR = 0.05, CFI = 0.96 and TLI = 0.94). The EP measure had high ac-ceptability, and the Cronbach alpha coefficients of the dimensions were between 0.59 and 0.72, except for temporality (0.30). The reliability of the full scale was 0.68, was sensitive and the EP profiles in women, youth, temporary workers and lower income countries were as expected. Conclusions: The EP measure constructed from the items available in the EPRES scale used in the II ECCTS questionnaire shows acceptable psychometric properties for epidemi-ological quantification of precarious employment in Central America (AU)

Nanostructured fibrin-based hydrogel membranes for use as an augmentation strategy in Achilles tendon surgical repair in rats.

Hydrogels are polymeric biomaterials characterised by their promising biological and biomechanical properties, which make them potential alternatives for use in tendon repair. The aim of the present study was to generate in vitro, and determine the therapeutic efficacy in vivo, of novel nanostructured fibrin-based hydrogels to be used as an augmentation strategy for the surgical repair of rat Achilles tendon injuries. Fibrin, fibrin-agarose and fibrin-collagen nanostructured hydrogels (NFH, NFAH and NFCH, respectively) were generated and their biomechanical properties and cell-biomaterial interactions characterised ex vivo. Achilles tendon ruptures were created in 24 adult Wistar rats, which were next treated with direct repair (control group) or direct repair augmented with the generated biomaterials (6 rats/group). After 4 and 8 weeks, the animals were euthanised for macroscopical and histological analyses. Biomechanical characterisation showed optimal properties of the biomaterials for use in tendon repair. Moreover, biological analyses confirmed that tendon-derived fibroblasts were able to adhere to the surface of the generated biomaterials, with high levels of viability and functionality. In vivo studies demonstrated successful tendon repair in all groups. Lastly, histological analyses disclosed better tissue and extracellular matrix organisation and alignment with biomaterial-based augmentation strategies than direct repair, especially when NFAH and NFCH were used. The present study demonstrated that nanostructured fibrin-collagen hydrogels can be used to enhance the healing process in the surgical repair of tendon ruptures.

Evaluation of myopic cornea lenticules. A histochemical and clinical correlation.

In this work, we have analyzed the main clinical and corneal histological parameters that may be associated to the spherical equivalent (SE), age and gender of individuals with myopic refractive errors. For this purpose, 108 cornea stroma lenticules were obtained from patients subjected to ReLEx-SMILE myopia correction. Histological analyses were carried out and histochemistry and immunohistochemistry were used to quantify key histological components of the cornea stroma, including mature collagen fibers, reticular and elastic fibers, glycoproteins, proteoglycans, type-V collagen and several crystallins. Clinical and histological data were analyzed to determine their association with SE, age and gender. Results showed a significant correlation between the age range of the patients and the expression of crystallins CRY-α-A, CRY-λ1 and type-V collagen and between CRY-λ1 and corneal thickness, spherical diopters (D) and SE, although correlation between CRY-λ1 and SE was non-significant when age was controlled. Comparison of cases with low myopia and high/moderate myopia found statistical differences for D and lenticule thickness and diameter. The binary logistic regression analysis allowed us to construct a model using two clinical parameters (D and lenticule thickness). Parameters showing significant correlation with the age were the corneal radius, keratometry reading (K), OZ, CRY-α-A and type-V collagen, whereas SE, lenticule thickness, OZ, CRY-λ1 and type-V collagen showed statistically significant differences between the youngest and the oldest patients. A binary logistic regression analysis model was generated including 3 variables (D, cornea radius and OZ). No gender differences were found. The specific clinical and histological modifications found to be associated to the SE and age could be useful for a better understanding of the mechanisms involved in the genesis or progression of myopia and could establish the basement for future therapeutic options.

Cierre de fístula oroantral con injerto de hueso vómer / Oroantral fistula with vomer bone graft clouser

Presentamos un caso de fístula oroantral y rinosinusitis maxilar, resuelto por abordaje combinado endoscópico, nasal e intraoral en el cual se utilizó colgajo de mucosa palatina y hueso vómer para el cierre de la misma. Describimos el caso de una paciente femenina de 66 años de edad, que consultó por presentar cacosmia, algia facial izquierda y rinorrea posterior purulenta, 3 semanas posterior a extracción de segundo molar superior izquierdo, la tomograffa axial computarizada (TC) de senos paranasales evidenció velamiento total maxilar izquierdo, parcial etmoidal izquierdo y defecto óseo en reborde alveolar superior izquierdo. Se realizó toma de fragmento de hueso vómer. Seguidamente abordaje de cavidad antral izquierda por vía endoscópica; e intraoral, se concluyó disección, cierre óseo y mucoso de la fístula.

We report a case of an oroantral fistula and maxillary rhinosinusitis, that was resolved by combined approach, in which palatal mucosa flap and vomer bone was used for its closure. We describe the case of a female patient of 66 years old, who consulted for having cacosmia, left facial pain and purulent rhinorrhea, after left second molar extraction. CT-scan sinus showed the total left maxillary sinus, partial left ethmoid opacity and bone defect in left alveolar ridge. A vomer bone graft was taken from the nasal septum; left maxillary sinus surgerywas done by endoscopic approach and intraoral closure of bony and mucosa fístula was concluded.

Pancreatoduodenectomía: experiencia, morbilidad y resultados / Pancreatoduodenectomy: experience, morbidity and results

Introducción: El 80% de los pacientes con cáncer de páncreas son diagnostcados en estadío tardío, y la sobrevida a los cinco años es menor del 2% sintratamiento. La resección quirúrgica parece ofrecer el único medio que extende la sobrevida hasta un 20% en el primer año, es necesario conocer lastasas de morbi-mortalidad en las insttuciones que cuentan con un equipo de cirujanos entrenados en cirugía hepatopancreatobiliar.Método: Se realizó una revisión retrospectva, observacional y descriptva de cinco años (2010-2015), de pacientes sometdos a pancreatoduodenectomíaspor cáncer de páncreas, determinando morbilidad y sobrevida. El análisis se dividió en dos períodos: Primer período 2010-2011 y el Segundoperíodo del 2012-2015.Resultados: Se analizaron 41 pacientes que presentaron 11(26.82%) complicaciones; cuatro fstulas pancreátcas y una fstula biliar consideradas comocomplicaciones mayores entre el primer período; el resto fueron por infección de herida operatoria reportadas en el segundo período, clasifcadascomo menores. Se reportaron tres (7.31%) casos de mortalidad durante el primer período. La sobrevida a los 5 años en nuestro estudio es 25%. Nose encontró diferencia en el promedio de complicaciones mayores, ni menores, ni de mortalidad entre el primer período y el segundo (p=0.18, p=0.1,p=0.25, respectvamente).Conclusión: Es necesario un razonable nivel de experiencia en pancreatoduodenectomías para alcanzar bajos niveles de morbi-mortalidad postoperatoria.

Background: At the tme of diagnosis, eighty percent of pancreatc cancer patents have advanced disease and a fve-year survival rate less than 2%without any treatment. Surgical resecton is the only treatment that extends survival rate to 20%. Every insttuton that performs pancreatc surgeriesneed to know their mortality rates.Methods: A retrospectve study of pancreatc cancer patents surgically treated from 2010 to 2015 in which pancreatoduodenectomy was performed.The morbidity, mortality and survival rate were analyzed divided by frst (2010-2011) and second (2012-2015) periods.Results: Forty one patents were analyzed. Complicaton rate was 26.82% (11/41): 5 major complicatons: 4 pancreatc fstulas and one biliary fstulapresented during the frst period. The rest were minor complicatons: surgical site infectons presented during the second period. Mortality rate was7.31% during the frst period. There was no mortality in the second period. Survival rate at 5 years was 25%. No statstcal diference was found for majoror minor complicaton rate nor for mortality between the frst or second period; (p=0.18, p=0.1, p=0.25, respectvely).Conclusions: Experience in pancreatoduodenectomy is necessary for low morbidity and mortality rates.

Análisis de asociación de los polimorfismos -725C>G (rs1233334), -201G>A (rs1233333) y 14 bp deleción/inserción (14-pb del/ins) (rs66554220) del gen HLA-G en mujeres mexicanas con pérdida gestacional recurrente / Analysis of association of polymorphisms -725C >G ( rs1233334 ), -201G >A ( rs1233333 ) and 14 bp deletion / insert (14 - bp / ins ) ( rs66554220 ) of HLA -G gene mexican women with recurrent pregnancy loss

Antecedentes: El antígeno leucocitario humano (HLA)-G es una molécula inmunomoduladora que contribuye a la aceptación del feto semialogénico. Algunos polimorfismos de un solo nucleótido (SNP) en las regiones no codificantes del gen HLA-G inducen a la disminución de moléculas HLA-G, lo cual contribuye a complicaciones en el embarazo, tales como la preeclampsia o pérdida gestacional recurrente. Objetivo: Analizar la asociación de los polimorfismos -725C>G (rs1233334), -201G>A (rs1233333) y 14 bp deleción/inserción (14-pb del/ins) (rs66554220) del gen HLA-G en mujeres mexicanas con PGR. Métodos: Los polimorfismos -725C>G (rs1233334), -201G>A (rs1233333) y 14-pb del/ins (rs66554220) se identificaron por medio de PCR-SSOP (Polymerase Chain Reaction-sequence-specific oligonucleotide probe) y PCR (Polymerase Chain Reaction), respectivamente, en 58 mujeres con pérdida gestacional recurrente (> 2 abortos), sin factores de riesgo identificables y 56 mujeres fértiles no relacionadas (> 2 nacidos vivos). Resultados: El polimorfismo -725C>G (rs1233334) presentó diferencias significativas entre los grupos de estudio pero no se asoció con PGR (p=0,02601; OR=11,484; IC95 por ciento =0,617-213,659). Los polimorfismos -201G>A (rs1233333) y 14-pb del/ins (rs66554220) no se distribuyeron de manera diferente entre los grupos de estudio ni se asociaron con pérdida gestacional recurrente. Los polimorfismos analizados se encontraron en equilibrio de ligamiento (D'>0,3563; r²<0,1140). Conclusión. Este estudio sugiere que los polimorfismos -725C>G (rs1233334), -201G>A (rs1233333) y 14-pb del/ins (rs66554220) del gen HLA-G están en equilibrio de ligamiento y no influyen en el riesgo de pérdida gestacional recurrente en mujeres mexicanas.

Background: The human leukocyte antigen (HLA)-G is an important immunomodulatory molecule that contributes to the acceptance of the semi-allogeneic fetus. Some single nucleotide polymorphisms (SNP) in the noncoding regions of the HLA-G gene may influence the cellular levels of HLA-G, contributing to pregnancy complications such as preeclampsia or recurrent pregnancy loss. Objective: To analyze the association of -725C>G (rs1233334),-201G>A (rs1233333) and 14 bp deletion/insertion (14-bp del/ins) (rs66554220) polymorphisms in the HLA-G gene in Mexican women with RPL. Methods: -725C>G (rs1233334), -201G>A (rs1233333) and 14-bp del/ins (rs66554220) polymorphisms in the HLA-G gene were identified by PCR-SSOP (polymerase chain reaction-sequence-specific oligonucleotide probe) and PCR (polymerase chain reaction), respectively, in 58 women with recurrent pregnancy loss (> 2 miscarriages) without identifiable risk factors and 56 unrelated fertile women (> 2 live births). Results: -725C>G (rs1233334) polymorphism showed significant differences between the study groups but it was not associated with recurrent pregnancy loss (p=0.02601, OR=11.484; 95 percent CI=0.617-213.659). -201G>A (rs1233333) and 14-bp del/ins (rs66554220) polymorphisms were not distributed differently in study groups and not associated with RPL. Analyzed polymorphisms were in linkage disequilibrium (D' > 0.3563, r² < 0.1140). Conclusion: This study suggests that -725C>G (rs1233334), -201G>A (rs1233333) and 14-pb del/ins (rs66554220) in the HLA-G gene are in linkage equilibrium and do not influence the risk of recurrent pregnancy loss in Mexican women.

Nonequilibrium and nonperturbative dynamics of ultrastrong coupling in open lines.

The time and space resolved dynamics of a qubit with an Ohmic coupling to propagating 1D photons is studied, from weak coupling to the ultrastrong coupling regime. A nonperturbative study based on matrix product states shows the following results, (i) The ground state of the combined systems contains excitations of both the qubit and the surrounding bosonic field. (ii) An initially excited qubit equilibrates through spontaneous emission to a state, which under certain conditions is locally close to that ground state, both in the qubit and the field. (iii) The resonances of the combined qubit-photon system match those of the spontaneous emission process and also the predictions of the adiabatic renormalization [A. J. Leggett et al., Rev. Mod. Phys. 59, 1 (1987)]. Finally, nonperturbative ab initio calculations show that this physics can be studied using a flux qubit galvanically coupled to a superconducting transmission line.

Quantum manipulation of trapped ions in two dimensional coulomb crystals.

We show that a large number of ions forming a 2D Coulomb crystal provides an almost ideal system for scalable quantum computation and quantum simulation. In particular, the coupling of the internal states to the motion of the ions transverse to the crystal plane allows one to implement two-qubit quantum gates. We analyze in detail the decoherence induced by anharmonic couplings, and show that very high gate fidelities can be achieved with current experimental setups.

Density matrix renormalization group and periodic boundary conditions: a quantum information perspective.

We introduce a picture to analyze the density matrix renormalization group (DMRG) numerical method from a quantum information perspective. This leads to a variational formulation of DMRG which allows for dramatic improvements in the case of problems with periodic boundary conditions. The picture also explains some features of the method in terms of entanglement and teleportation.

Effective quantum spin systems with trapped ions.

We show that the physical system consisting of trapped ions interacting with lasers may undergo a rich variety of quantum phase transitions. By changing the laser intensities and polarizations the dynamics of the internal states of the ions can be controlled, in such a way that an Ising or Heisenberg-like interaction is induced between effective spins. Our scheme allows us to build an analogue quantum simulator of spin systems with trapped ions, and observe and analyze quantum phase transitions with unprecedented opportunities for the measurement and manipulation of spins.

Bose-Einstein condensation and strong-correlation behavior of phonons in ion traps.

We show that the dynamics of phonons in a set of trapped ions interacting with lasers is described by a Bose-Hubbard model whose parameters can be externally adjusted. We investigate the possibility of observing several quantum many-body phenomena, including Bose-Einstein condensation as well as a superfluid-Mott insulator quantum phase transition.

Evaluación toxicológica en ratas Sprague-Dawley de Interleuquina-2 y del candidato vacunal FPCR3, terapia combinada en pacientes con SIDA / Toxicological evaluation of Interleukin-2 and FPCR3 vaccine candidate in Sprague-Dawley rats, combined therapy in AIDS-patients

En busca de nuevas fórmulas terapéuticas para combatir la infección por el virus de inmunodeficiencia humana se han desarrollado diferentes tipos de vacunas, entre las que se encuentran las que estimulan la respuesta de linfocitos T citotóxicos contra antígenos del VIH. A partir de la obtención en el Centro de Ingeniería Genética y Biotecnología (La Habana, Cuba) de un candidato vacunal que utiliza como vector el virus de la viruela aviar modificado con genes que expresan proteínas anti-VIH, se ha diseñado un estudio clinico que combina la aplicación de este producto (FPCR3) con la terapia antirretroviral de alta eficiencia y dosis bajas de Interleuquina-2 humana recombinante (IL-2hr). Antes de ensayar estos productos biotecnológicos en pacientes con el síndrome de inmunodeficiencia adquirida se hizo necesario realizar pruebas toxicológicas para evaluar su seguridad, para lo cual se diseñaron 2 estudios de toxicidad aguda en los que se evaluó la respuesta sistémica y local de ratas Sprague-Dawley a dosis superiores a la que se administrará en los pacientes incluidos en el estudio clínico piloto. Se utilizaron 50 ratas de la sublínea Cenp: SPRD (Sprague-Dawley) en el estudio de toxicidad aguda de Interleuquina-2hr y 70 animales de esta misma especie y sublínea para el realizado al candidato vacunal FPCR3. Los productos Se administraron por vía subcutánea e intramuscular respectivamente a niveles de 30, 60 y 90 veces la dosis terapéutica. En el estudio realizado al candidato vacunal FPCR3 se incluyeron 3 grupos en los que se realizaron administraciones repetidas, a fin de evaluar de forma preliminar la tolerancia local de este producto. En ambos estudios se incluyó un grupo control inoculado con el placebo de las formulaciones. Se realizó Observación clínica diaria y se llevó a cabo el estudio histopatológico de los órganos diana y del sitio de administración. No se evidenciaron signos de toxicidad ni efectos adversos en los animales inoculados con el candidato vacunal FPCR3 é IL-2. No se reportaron muertes durante los estudios y los animales manifestaron adecuada respuesta ante estímulos, así como incremento progresivo de peso. El estudio histopatológico mostró ligera reacción local caracterizada por secuestro del inóculo y presencia de tejido de granulación en animales administrados con Interleuquina-2 hr. En los que recibieron diferentes dosis del candidato vacunal FPCR3 se reportaron granulomas macrofágicos de diversa intensidad en el sitio de administración. No se reportó en ningún caso signos de toxicidad en los órganos estudiados. Aún cuando se precisan otros estudios toxicológicos, estos resultados sugieren que la aplicación del candidato vacunal FPCR3 contra el virus de la inmunodeficiencia humana -y de Interleuquina-2hr es segura y bien tolerada en el espectro de dosis estudiadas, garantizando un marco de segur¡dad adecuado para su aplicación en los pacientes infectados con el síndrome de la inmunodeficiencia adquirida incluidos en el estudio clínico piloto (AU)

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Superoinferior ventricles with superior left ventricle and inferior right ventricle: a newly recognized form of congenital heart disease.

We report the first known case of supero-inferior ventricles with a superior morphologically left ventricle and an inferior morphologically right ventricle. This 2 1/2-year-old boy also had dextrocardia, double-outlet right ventricle [S,L,L], right-sided mitral atresia, left-sided tricuspid regurgitation, a large conoventricular type of ventricular septal defect, and pulmonary outflow tract stenosis. This very rare form of superoinferior ventricles appears to be due to excessive levorotation (approximately equal to 170 degrees) of discordant L-loop ventricles.

Distributed computing for membrane-based modeling of action potential propagation.

Action potential propagation simulations with physiologic membrane currents and macroscopic tissue dimensions are computationally expensive. We, therefore, analyzed distributed computing schemes to reduce execution time in workstation clusters by parallelizing solutions with message passing. Four schemes were considered in two-dimensional monodomain simulations with the Beeler-Reuter membrane equations. Parallel speedups measured with each scheme were compared to theoretical speedups, recognizing the relationship between speedup and code portions that executed serially. A data decomposition scheme based on total ionic current provided the best performance. Analysis of communication latencies in that scheme led to a load-balancing algorithm in which measured speedups at 89 +/- 2% and 75 +/- 8% of theoretical speedups were achieved in homogeneous and heterogeneous clusters of workstations. Speedups in this scheme with the Luo-Rudy dynamic membrane equations exceeded 3.0 with eight distributed workstations. Cluster speedups were comparable to those measured during parallel execution on a shared memory machine.