Abstract In this investigation thermochemical properties of 3-hydroxyphthalic anhydride were determined. Fusion enthalpy, fusion temperature and molar heat capacity in solid phase were obtained by differential scanning calorimetry. By the Knudsen effusion method, the molar enthalpy of sublimation at 298.15 K was obtained. By thermogravimetric data, it was possible to determine the molar enthalpy of sublimation and the molar enthalpy of vaporization. On the other hand, the molar enthalpy of formation in solid phase at 298.15 K was determined by combustion calorimetry. The molar enthalpy of formation in gas phase at 298.15 K was calculated from molar enthalpy of sublimation at 298.15 K and molar enthalpy of formation in solid phase at 298.15 K. This experimental value was compared both theoretical enthalpy of formation in gas phase by using Gaussian methods at the G3 and G4 levels and with an estimated value in relation to phthalic anhydride.

Abstract This work proposes a photonic method to generate optical pulses with a triangular wave shape using a low coherence source. We modulate this source using a sinusoidal radio frequency signal as a local oscillator. We eliminate the second harmonic of the spectral components generated by the modulation process tuning a reject filter to get a triangular wave. We implement the filter using an interferometer with a delay line in one of their branches. To tune the filter, the only adjustment required is over the optical delay line. We developed our scheme in a simulation environment but based on the use of optical and optoelectronic elements with parameters of commercial devices, some of them available in our laboratory. We generate triangular waveform signals with pulse frequencies of 100, 150, 250, and 300 MHz as proof of concept. The proposed scheme has the advantage of being low cost and easy to use because it does not require bias control nor adjustment to V π voltage. Usually, other authors must vary these parameters to get the desired electrical signal. Still, we generate the triangular waveform by adjusting only the local oscillator frequency and the optical delay line. Therefore, because we use a broad-spectrum optical source and do not require a strictly controlled variable voltage, our system will be cheaper.

Abstract The lepton sector is studied within a flavored non-renormalizable model where the S3⊗Z2 flavor symmetry controls the masses and mixings. In this work, the effective neutrino as well as the charged lepton mass matrices are hierarchical and these have (under a benchmark in the charged sector) a kind of Fritzsch textures that accommodate the mixing angles in good agreement with the last experimental data. The model favors the normal hierarchy, this also predicts consistent values for the CP-violating phase and the |mee| effective Majorana neutrino mass rate. Along with this, the branching ratio for the lepton flavor violation process, µ → eγ, is below the current bound.

Resumen El objetivo de este estudio fue establecer los diagnósticos de los pacientes con eccema diseminado y analizar los alérgenos implicados en el eccema diseminado por dermatitis alérgica de contacto. Para ello, se analizaron los datos de los pacientes con diagnóstico de eccema diseminado/generalizado a los que se les había realizado anamnesis, exploración física y pruebas epicutáneas en una consulta de Dermatitis de Contacto en el periodo 2003-2019. El diagnóstico más frecuente fue dermatitis alérgica de contacto, seguido de dermatitis atópica, eccema asteatósico y eccema gravitacional. Los alérgenos más frecuentemente implicados en dermatitis de contacto alérgica fueron las isotiazolinonas, los medicamentos tópicos, la parafenilendiamina y las fragancias. La dermatitis alérgica de contacto causó casi la mitad de los casos de eccema diseminado. Por ello, consideramos conveniente que los pacientes con eccema diseminado sean valorados en una Unidad de Contacto y se sometan a la realización de pruebas epicutáneas.

Abstract The aim of this study was to establish the diagnoses of patients with disseminated eczema and analyze the allergens involved in disseminated eczema due to allergic contact dermatitis. We analyzed the data from patients with a diagnosis of disseminated / generalized eczema who had undergone anamnesis, physical examination and patch tests in a Contact Dermatitis consultation from 2003 to 2019. Allergic contact dermatitis was the most frequent diagnosis, followed by atopic dermatitis, asteatotic eczema, and gravitational eczema. The allergens most frequently involved in allergic contact dermatitis were isothiazolinones, topical medications, paraphenylenediamine, and fragrances. Allergic contact dermatitis caused almost half of the cases of disseminated eczema. It would be therefore advisable for patients with disseminated eczema to be assessed at a Contact Dermatitis unit and undergo patch tests.

ABSTRACT Background: One of the impact indicators of priorities in health research-setting is the scientific production that refers to these priorities. EsSalud raised nine priority research topics (PRT) and 20 priority research questions (PRQ) for the 2017-2019 period. We assess the alignment to these research priorities in the scientific articles published during the 2017-2020 period by EsSalud, and we characterize those financed by this institution. Material and Methods: Analysis of the scientific articles registered in the EsSalud scientific production database for the period 2017-2020. We used a standardized methodology and in duplicate to evaluate the alignment of a scientific article to the PRT and PRQ 2017-2019 of EsSalud. The evaluation of the alignment to the PRQs is only carried out in original articles and congress summaries. We report alignment frequencies to each PRT and PRQ, and we report the frequency of alignment to at least one PRT according to the articles' characteristics. In addition, the characteristics of the articles financed by EsSalud were reported. Results: 170 out of 1283 articles were aligned to at least one PRT. Eight of the twenty PRQs went unanswered. Articles with authors who belong to or received funding from IETSI-EsSalud had the highest alignment rate. Finally, the highly cited articles financed by EsSalud were mainly observational studies, clinical practice guidelines and systematic reviews. Conclusion: The articles published by EsSalud during 2017 to 2020 have low alignment with institutional research priorities. Furthermore, it is necessary a process of implementation, monitoring, and evaluation of research priorities in the institution.

RESUMEN Introducción: Uno de los indicadores del impacto del establecimiento de prioridades en investigación en salud es la producción científica. EsSalud planteó nueve temas de investigación prioritarios (TIP) y 20 preguntas de investigación prioritarias (PIP) 2017-2019. Evaluamos el alineamiento a estas prioridades de investigación en los artículos científicos publicados con filiación de EsSalud durante 2017-2020, y caracterizamos aquellos financiados por esta institución. Material y Métodos: Análisis de los artículos científicos registrados en la base de datos de producción científica de EsSalud 2017-2020. Empleamos una metodología estandarizada y por duplicado para evaluar el alineamiento a los TIP y PIP 2017-2019 de EsSalud. La evaluación del alineamiento a las PIP sólo lo realizamos en artículos originales y resúmenes de congreso. Reportamos frecuencias de alineamiento a cada TIP y PIP, y frecuencia de alineamiento a por lo menos un TIP según características de los artículos. Además, se reportó las características de los artículos financiados por EsSalud. Resultados: Un total de 170 de 1283 artículos se alinearon a al menos un TIP. Ocho de las veinte PIP no fueron respondidas. Los artículos con autores que pertenecen o recibieron financiamiento del IETSI-EsSalud tuvieron la mayor tasa de alineación. Finalmente, los artículos financiados por EsSalud fueron principalmente estudios observacionales, guías de práctica clínica y revisiones sistemáticas. Conclusión: Los artículos científicos publicados con filiación de EsSalud durante el 2017 al 2020 tienen baja alineación con las prioridades de investigación de la institución. Por lo tanto, es necesario generar un proceso de gestión de implementación, seguimiento y evaluación de las prioridades de investigación en la institución.

Abstract We report a Costas loop for demodulation of an optical field with binary phase modulation (BPSK). The loop operates in the domain of digital signal processing (DSP) as part of an intradyne coherent digital receiver. The practical implementation of BPSK demodulation in the optical domain is generally not feasible. For this reason, we use techniques based on high-speed digitization of the post-photodetection electrical observable, and the Costas loop in DSP acts on the digitized signal. We chose this loop because it is an optimal structure for both BPSK demodulation and carrier synchronization. Typically, Costas loops for BPSK demodulation operate on a carrier with a frequency higher than the bit rate. However, as we demonstrate in this work, this loop can also perform adequately for a bit rate higher than the carrier frequency (intradyne detection). To the best of our knowledge, the Costas loop in DSP for intradyne BPSK demodulation is reported for the first time in this work. To design the intradyne Costas loop, we used the PLL-equivalent model of a conventional Costas loop. For comparison and performance evaluation, we implemented in simulation, first, a traditional Costas loop and later an intradyne one. We use real-world signals (binary data and additive noise) acquired by digitization for our simulations. Finally, we performed the intradyne Costas loop’s characterization using a digitized post-photodetection electrical signal obtained at the output of our digital coherent receiver. We observe a performance very close to that obtained by simulation.

Resumen Reportamos un lazo de Costas para demodulación de un campo óptico con modulación de fase binaria (BPSK). El lazo opera en el dominio del procesamiento digital de señales (DSP) como parte de un receptor digital coherente intradino. Generalmente, la implementación práctica de demodulación BPSK en el dominio óptico no es factible. Por ello, empleamos técnicas basadas en la digitalización a alta velocidad del observable eléctrico post-fotodetección y el lazo de Costas en DSP actúa sobre la señal digitalizada. Elegimos este lazo por ser una estructura óptima tanto de demodulación BPSK como de sincronización de portadora. Normalmente, los lazos de Costas para demodulación BPSK operan con una portadora con frecuencia mayor que la velocidad del bit. Sin embargo, como demostramos en este trabajo, este lazo también puede operar adecuadamente para una velocidad de bit mayor que la frecuencia de portadora (detección intradina). A lo mejor de nuestro conocimiento, el lazo de Costas en DSP para demodulación BPSK intradina se reporta por primera vez en este trabajo. Para el diseño del lazo de Costas intradino nos basamos en el modelo PLL equivalente de un lazo de Costas convencional. Con fines de comparación y evaluación del desempeño, primero implementamos en simulación, un lazo de Costas tradicional y posteriormente, uno intradino. Para nuestras simulaciones, empleamos señales del mundo real (datos binarios y ruido aditivo) adquiridas mediante digitalización. Finalmente, se realizó la caracterización del lazo de Costas intradino empleando una señal eléctrica post-fotodetección digitalizada obtenida a la salida de nuestro receptor digital coherente. Se observó un desempeño muy cercano al obtenido mediante simulación.

Abstract In this article, the statistical evaluation of the performance of FSO links subject to dynamic fluctuations of atmospheric optical turbulence that affect the instantaneous value of the received optical power is presented. We reproduce this temporal domain effect with time series generated by simulation considering the optical turbulence as a stochastic process with Gamma-Gamma probability distribution. Also, a phase screen was used in order to observe the impact that optical turbulence has over the optical information field’s spatial phase. With our simulations, it is possible to get the two most essential performance parameters required for the practical implementation of FSO links. We obtained the mean signal-to-noise ratio (SNR) and the mean bit error rate (BER) of FSO links affected by optical turbulence with Gamma-Gamma distribution, where the results show that the mean SNR and mean BER are adequately modified according to the atmospheric turbulence levels, e.g., ≈ 1.4 dB for σ R 2 = 0.33 and ≈ 0.36 dB for σ R 2 = 1. Thus, the methodology presented in this paper may be readily used to design and implement real-world FSO links.

Abstract We numerically study the percolation in 3D porous materials, populated by pores with random sizes on 3D grid of variable sizes. We identify the clusters for each grid as well as the infinite cluster that is defined by the critical probability through the neighborhood hybrid structure method. We also determine the characteristic size of each cluster in the material as well as the volume of the infinite cluster that allows optimizing the percolation step at our simulation. In this work, several tests were performed changing the size of the grid. This allows us to determine the optimal size and how it affects the percolation by the simulating grids. Our main results show that in systems with pores having random radii the critical probability increases when size of grid L > 40 (that correspond to typical size system about 4000 nm) with respect of the case with uniform pores.

Abstract Pt (0.5, 1 and 1.5 wt%) was impregnated by incipient wetness on SBA-15 and corresponding Ga-modified (3, 5, 10 and 20 wt%) composites. Gallium nitrate was incorporated directly during the mesoporous siliceous network synthesis. Materials were characterized by N2 physisorption, X-ray diffraction, Fourier transformed infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. SBA-15 had surface area greater than 800 m²/g that decreased by Ga incorporation in binary materials. It seemed that tetrahedral gallium was well-incorporated into mesoporous silica walls. Pt dispersion slightly diminished (as to that on SBA-15) by augmenting Ga concentration in composites. Corresponding pore size maxima shifted to lower diameters (as to that of non-impregnated supports) after platinum loading suggesting Pt crystals inside pores of SBA-15 and Ga-modified carriers. Large cubic platinum crystals were observed over all prepared materials probably due to sintering (during calcining at 500 °C) of metallic particles weakly interacting with the carriers surface. After materials annealing (500 °C under static air) metallic platinum was evidenced (by XRD) pointing out to noble metal reduction that could be facilitated by decomposition of organic remains from Si alkoxide used during supports synthesis which presence was ascertained by FTIR.

Abstract Background To describe the dermoscopic features in superficial basal cell carcinoma that are associated with a poor therapeutic response to imiquimod treatment. Method Clinical and dermatoscopic photographs of 56 superficial basal cell carcinomas of different patients were compared retrospectively, assessed in our office for five years and treated with topic 5% imiquimod five days a week for six weeks. The different dermatoscopic signs of the lesions were identified and the association of each of them with the response to treatment was assessed. Results A total response to treatment was achieved by 69.5% of the lesions of patients treated with imiquimod. Dermatoscopy of responding lesions showed a higher frequency of lesions with in focus gray dots (43.6%) and multiple erosions of less than 2 mm (61.5%), without observing statistically significant differences. Within the group with poor response to treatment, a greater number of lesions were found with the presence of arborizing telangiectasias (58.8%), blue-gray ovoid nests (41.1%), ulceration (58.8%), shiny white-red structureless areas (82.2%) and chrysalis (41.2%). The areas in blue-white veil areas (23.5%) and rainbow pattern (23.5%) were only observed in non-responding lesions. Both groups were similar regarding age, sex, diameter of lesions and frequency of some dermatoscopic signs: fine short telangiectasias, gray blue globules, arc-leaf areas and cart-wheel structures. Conclusion The study identified dermatoscopic criteria that are significantly associated with a worse response to treatment with imiquimod. In contrast, we found no dermatoscopic signs that correlate specifically to a complete response to treatment.

Resumen Fundamento Identificar los signos dermatoscópicos de los carcinomas basocelulares superficiales que se asocien a una peor respuesta completa al tratamiento con imiquimod. Método Se compararon de forma retrospectiva fotografías clínicas y dermatoscópicas de 56 carcinomas basocelulares superficiales de diferentes pacientes, valorados en consulta durante cinco años y tratados con imiquimod tópico al 5% cinco días a la semana durante seis semanas. Se identificaron los diferentes signos dermatoscópicos de las lesiones y se valoró la asociación de cada uno de ellos con la respuesta al tratamiento. Resultados Un 69,5% de los pacientes respondieron al tratamiento con imiquimod. La dermatoscopia de lesiones respondedoras mostró una frecuencia mayor de lesiones con puntos grises en foco (43,6%) y de erosiones múltiples menores de 2 mm (61,5%), sin observar diferencias estadísticamente significativas. El grupo sin respuesta mostró más telangiectasias arboriformes (58,8%), nidos ovoides (41,1%), ulceraciones (58,8%), áreas desestructuradas brillantes rojas-blancas (82,2%) y crisálidas (41,2%). Las áreas en velo azul-blanco (23,5%) y de patrón en arco iris (23,5%) solo se observaron en no respondedores. Ambos grupos fueron similares respecto a edad, sexo, diámetro de las lesiones y frecuencia de algunos signos dermatoscópicos: telangiectasias cortas finas, glóbulos azul-grises, áreas en hoja de arce y estructuras en rueda de carro. Conclusión Se identificaron criterios dermatoscópicos que se asocian de manera significativa a una peor respuesta al tratamiento con Imiquimod. En cambio, no se encontraron signos dermatoscópicos que se correlacionen de manera específica a una respuesta completa al tratamiento.

Abstract: Since verbal communication is used as the primary learning means, acoustics became one of the most important attributes of classroom architectural design. Adverse acoustic conditions in the classroom negatively affect the students’ learning, achievement and cognitive development. In 2015, the Chilean Ministry of Education introduced acoustic design criteria for educational buildings. This paper presents a review of these criteria by comparing them with international standards and considering the database of the urban noise map of Santiago. The results show shortcomings in the current acoustic criteria for learning environments in Chile, in relation to international standards. Furthermore, they indicate that, with the current urban noise levels, the acoustic design criteria for learning environments of the Ministry of Education cannot be applied to more than 70% of the educational institutions in Santiago.

Resumen: Desde que la comunicación oral es el principal medio que utilizamos para aprender, la acústica se vuelve uno de los atributos más importantes del diseño arquitectónico de las aulas. Las condiciones acústicas adversas en las aulas afectan negativamente el aprendizaje, el desempeño y el desarrollo cognitivo de los estudiantes. En el año 2015 el Ministerio de Educación introdujo criterios de diseño acústico para los espacios educativos. Este artículo presenta una revisión de dichos criterios realizada mediante una comparación con la normativa internacional y considerando la base de datos del mapa de ruido urbano de Santiago. Los resultados muestran que los actuales criterios acústicos para los espacios educativos en Chile presentan falencias con respecto a la normativa internacional. Además, se observa que, con los actuales niveles de ruido urbano, el criterio de diseño acústico para los espacios educativos del Ministerio de Educación no se puede aplicar a más del 70% de los establecimientos educacionales en Santiago.

Abstract Low acidity catalytic formulations were prepared incorporating MgO and Li2O to the conventional CoMoW/Al2O3 catalysts. The CoMoW active phases were impregnated using an ammoniacal solution containing the metallic complexes as citrates. A high dispersion of the Co, Mo and W species in octahedral coordination, inhibiting the agglomeration towards phases like MoO3, WO3 and Co3O4, was attained. The obtained formulations preserve the catalytic activity in the hydrodesulphurization (HDS) reaction of dibenzothiophene (DBT), enhancing the selectivity towards the direct desulphurization route. The prepared formulations show a lower hydrogenation function due to its low acidity.

Abstract In this paper, an adaptive low density parity check (LDPC). encoder for complete Free Space Optics/Continuous Variable-Quantum Key Distribution (FSO/CV-QKD) system using a Commercially available Off-The-Shelf (COTS) device for emulated dynamical atmospheric turbulence levels is presented. The experimental and emulation results show the maximum and minimal final secret key rates of ≈ 105 Kbps and ≈ 10 Kbps, respectively, for minimal and maximal throughput in a commercial network, 30 Mbps and 90 Mbps, respectively. Our proposal presents an adequate performance for weak and moderate atmospheric turbulence levels and a suitable option for improving the use of Quantum Key Distribution (QKD) systems.

Foreword The presence of formaldehyde at workplace remains significant. Exposure to it results in local irritation of the eye, nose and upper respiratory tract mucous membranes, and it has been chronically related to a higher risk of cancer development at the paranasal sinuses, naso-oropharynx and lungs. The aim of our work has been the updating of the bibliography and the categorization of the most up to date scientific evidence of formaldehyde effects on human body. Bibliographic search on the electronic database Medline / PubMed, restricted to the last 10 years through a combination of free and controlled language.Review of 185 scientific articles, finally including 54 due to duplicity, language, and inclusion criteria. We find among the main results a major evidence regarding genotoxicity; limited, inconsistent, and contradictory evidence regarding various neoplastic pathologies; and lack of evidence regarding bronchial asthma. Further studies have to be carried out, especially longitudinal studies and greater epidemiological power, to generate new knowledge about the behavior of this toxic.

Resum Introducció: La presència del formaldehid a l’àmbit laboral segueix sent important. L’exposició produeix irritació local de mucoses, com ara les oculars, nasals i del tracte respiratori superior i de manera crònica s’ha associat amb un major risc de desenvolupar càncer a nivell de mucosa i sinus paranasals, naso-orofaringe i pulmó. L’objectiu del nostre treball ha estat actualitzar la bibliografia i categoritzar l’evidència científica més actualitzada dels efectes que el formaldehid produeix sobre l’organisme humà. Mètode: Revisió de la literatura utilitzant la metodologia “scoping review”. Cerca bibliogràfica a la base de dades electrònica Medline/ PubMed, limitada als darrers 10 anys mitjançant combinació de llenguatge lliure i controlat. Anàlisi efectuada per un col.lectiu de Metges especialistes en medicina del treball, pertanyents a l’àmbit sanitari i que també han comptat amb la participació d’higienistes i altres professionals de la prevenció de riscos. Resultats: Revisió de 185 articles, amb inclusió final de 54 un cop descartats per duplicitat, idioma i criteris d’inclusió. Entre els principals resultats es troba un elevat grau d’evidència referida a genotoxicitat, evidència contradictòria, inconsistent o limitada pel que fa a diverses patologies neoplàsiques d’origen hematopoiètic, laringe, naso-sinusals o de pulmó i manca d’evidència sobre la relació amb l’asma bronquial. Conclusions: La revisió mostra un canvi de paradigma dels efectes del formaldehid sobre l’organisme humà, amb dades que qüestionen els efectes tòxics clàssicament admesos. Cal efectuar nous estudis, especialment amb caràcter longitudinal i major potència epidemiològica, per generar nou coneixement sobre el comportament d’aquest tòxic.

Resumen La presencia del formaldehido en el ámbito laboral sigue siendo importante. La exposición produce irritación local de mucosas oculares, nasales y del tracto respiratorio superior, y crónicamente se ha asociado con mayor riesgo de desarrollar cáncer a nivel de senos paranasales, naso-orofaringe y pulmón. Esta revisión tiene por objetivo actualizar la bibliografía y categorizar la evidencia científica más actualizada de los efectos que el formaldehido produce sobre el organismo humano. Búsqueda bibliográfica en la base de datos electrónica Medline/PubMed, limitada a los últimos 10 años mediante combinación de lenguaje libre y controlado. Se revisaron 185 artículos con inclusión final de 54 tras descartar por duplicidad, idioma y criterios de inclusión. Se observa un elevado grado de evidencia respecto a la genotoxicidad, evidencia contradictoria, inconsistente o limitada respecto a patologías neoplásicas de origen hematopoyético, laringe, naso-sinusales o de pulmón y falta de evidencia sobre la relación con el asma bronquial. Es preciso efectuar nuevos estudios, especialmente con carácter longitudinal y mayor potencia epidemiológica, para generar nuevo conocimiento sobre el comportamiento de este tóxico.

Abstract: The objective of this study was to evaluate the influence of the site quality on the growth and increase of a Pinus patula plantation in Ixtlán de Juárez, Oaxaca. In a plantation established in 1995, there were thirty 400 m2 sites systematically distributed for carrying out a forest inventory of the trees. Dendrometric variables were measured and growth cores were extracted from two dominant trees at each site in order to obtain the mean annual increment (MAI), the current annual increment (CAI) and the ring width in the early and late wood. With data on the height and age of trees from the plantation and natural forest, functions were adjusted to estimate the site index (SI) by using the curve method with a baseline age of 40 years. Analysis of variance was performed using site qualities as a classification variable, and the increase in early and late wood was estimated by means of regression models. The quality of the site influences the dasometric and growth variables in P. patula (p = 0.0001). In addition, the total ring width for a low and an excellent SI was found to be 5 and 8.85 mm, respectively. Increases in early and late wood are positively correlated with the site quality (p = 0.0001). Therefore, the specific gravity of the wood is lower in higher quality sites. The optimal growth for the early and late wood varies in relation to the site quality. The increase and growth of Pinus patula is determined by the site quality.

Resumen El objetivo del presente estudio fue evaluar la influencia de la calidad de sitio sobre el crecimiento e incremento de una plantación de Pinus patula en Ixtlán de Juárez, Oaxaca, establecida en 1995. Se distribuyeron, sistemáticamente, 30 sitios de 400 m2 para realizar inventario del arbolado. Se consideraron variables dendrométricas, y a dos árboles dominantes de cada sitio se les extrajo una viruta para obtener el incremento medio anual (IMA), el incremento corriente anual (ICA) y el ancho de anillos en madera temprana y tardía. Con la información de altura y edad de la plantación y bosque natural, se ajustaron funciones para estimar el índice de sitio (IS) con el método de la curva guía a una edad base de 40años. Se realizaron análisis de varianza utilizando como variable clasificatoria la calidad de sitio, se estimó el incremento en madera temprana y tardía mediante modelos de regresión. La calidad de sitio influye en variables dasométricas y de crecimiento en P. patula (p = 0.0001); se determinó que el ancho total de anillo en IS bajo y excelente fue de 5 vs. 8.85 mm, respectivamente. Los incrementos en madera temprana y tardía están positivamente correlacionados con la calidad del sitio (p = 0.0001); por lo tanto, la gravedad específica de la madera es menor en sitios de mayor calidad. El crecimiento óptimo para las variables madera temprana y tardía varía en relación a la calidad del sitio. El crecimiento e incremento de Pinus patula está determinado por la calidad de sitio.