Optoelectronic Response to the Fluor Ion Bond on 4-(4,4,5,5-Tetramethyl-1,3,2-dioxoborolan-2-yl)benzaldehyde.

Boronate esters are a class of compounds containing a boron atom bonded to two oxygen atoms in an ester group, often being used as precursors in the synthesis of other materials. The characterization of the structure and properties of esters is usually carried out by UV-visible, infrared, and nuclear magnetic resonance (NMR) spectroscopic techniques. With the aim to better understand our experimental data, in this article, the density functional theory (DFT) is used to analyze the UV-visible and infrared spectra, as well as the isotropic shielding and chemical shifts of the hydrogen atoms 1H, carbon 13C and boron 11B in the compound 4-(4,4,5,5-tetramethyl-1,3,2-dioxoborolan-2-yl)benzaldehyde. Furthermore, this study considers the change in its electronic and spectroscopic properties of this particular ester, when its boron atom is coordinated with a fluoride anion. The calculations were carried out using the LSDA and B3LYP functionals in Gaussian-16, and PBE in CASTEP. The results show that the B3LYP functional gives the best approximation to the experimental data. The formation of a coordinated covalent B-F bond highlights the remarkable sensitivity of the NMR chemical shifts of carbon, oxygen, and boron atoms and their surroundings. Furthermore, this bond also highlights the changes in the electron transitions bands n → π* and π → π* during the absorption and emission of a photon in the UV-vis, and in the stretching bands of the C=C bonds, and bending of BO2 in the infrared spectrum. This study not only contributes to the understanding of the properties of boronate esters but also provides important information on the interactions and responses optoelectronic of the compound when is bonded to a fluorine atom.

Disparate response of decapods to low pH: A meta-analysis of life history, physiology and behavior traits across life stages and environments.

We employed a meta-analysis to determine if the presumed resilience of decapods to ocean acidification extends to all biological aspects, environments, and life stages. Most response categories appeared unaffected by acidification. However, certain fitness-related traits (growth, survival, and, to some extent, calcification) were impacted. Acid-base balance and stress response scaled positively with reductions in pH, which maintains homeostasis, possibly at the cost of other processes. Juveniles were the only stage impacted by acidification, which is believed to reduce recruitment. We observed few differences in responses to acidification among decapods inhabiting contrasting environments. Our meta-analysis shows decapods as a group slightly to moderately sensitive to low pH, with impacts on some biological aspects rather than on all specific life stages or habitats. Although extreme pH scenarios may not occur in the open ocean, coastal and estuarine areas might experience lower pH levels in the near to medium future, posing potential challenges for decapods.

Cortical astrocyte N-methyl-D-aspartate receptors influence whisker barrel activity and sensory discrimination in mice.

Astrocytes express ionotropic receptors, including N-methyl-D-aspartate receptors (NMDARs). However, the contribution of NMDARs to astrocyte-neuron interactions, particularly in vivo, has not been elucidated. Here we show that a knockdown approach to selectively reduce NMDARs in mouse cortical astrocytes decreases astrocyte Ca2+ transients evoked by sensory stimulation. Astrocyte NMDAR knockdown also impairs nearby neuronal circuits by elevating spontaneous neuron activity and limiting neuronal recruitment, synchronization, and adaptation during sensory stimulation. Furthermore, this compromises the optimal processing of sensory information since the sensory acuity of the mice is reduced during a whisker-dependent tactile discrimination task. Lastly, we rescue the effects of astrocyte NMDAR knockdown on neurons and improve the tactile acuity of the animal by supplying exogenous ATP. Overall, our findings show that astrocytes can respond to nearby neuronal activity via their NMDAR, and that these receptors are an important component for purinergic signaling that regulate astrocyte-neuron interactions and cortical sensory discrimination in vivo.

Osteoblastic Cell Behavior and Gene Expression Related to Bone Metabolism on Different Titanium Surfaces.

The surface topography of titanium dental implants has a great influence on osseointegration. In this work, we try to determine the osteoblastic behavior and gene expression of cells with different titanium surfaces and relate them to the physicochemical properties of the surface. For this purpose, we have used commercial titanium discs of grade 3: as-received corresponds to machined titanium without any surface treatment (MA), chemically acid etched (AE), treated via sand blasting with Al2O3 particles (SB) and a sand-blasting treatment with acid etching (SB+AE). The surfaces have been observed using scanning electron microscopy (SEM) and the roughness, wettability and surface energy with dispersive and polar components have been characterized. Osteoblastic cultures were performed with SaOS-2 osteoblastic cells determining cell viability as well as alkaline phosphatase levels for 3 and 21 days, and osteoblastic gene expression was determined. The roughness values of the MA discs was 0.02 µm, which increases to 0.3 µm with acid attack and becomes the maximum for the sand-blasted samples, reaching values of 1.2 µm for SB and SB+AE. The hydrophilic behavior of the MA and AE samples with contact angles of 63° and 65° is superior to that of the rougher samples, being 75° for SB and 82° for SB+AE. In all cases, they show good hydrophilicity. GB and GB+AE surfaces present a higher polar component in the surface energy values, 11.96 and 13.18 mJ/m2, respectively, than AE and MA, 6.64 and 9.79 mJ/m2, respectively. The osteoblastic cell viability values at three days do not show statistically significant differences between the four surfaces. However, the viability of the SB and SB+AE surfaces at 21 days is much higher than that of the AE and MA samples. From the alkaline phosphatase studies, higher values were observed for those treated with sand blasting with and without acid etching compared to the other two surfaces, indicating a greater activity in osteoblastic differentiation. In all cases except in the Osterix (Ostx) -osteoblast-specific transcription factor-a decrease in gene expression is observed in relation to the MA samples (control). The most important increase was observed for the SB+AE condition. A decrease in the gene expression of Osteoprotegerine (OPG), Runt-related transcription factor 2 (Runx2), Receptor Activator of NF-κB Ligand (RANKL) and Alkaline Phosphatase (Alp) genes was observed in the AE surface.

Motivos intrínsecos, extrínsecos y expectativas para elección de la carrera, como predictores de rendimiento académico en estudiantes de enfermería / Intrinsic and extrinsic motivations and expectations for career choice, as predictors of academic performance in nursing students

[{"text": "INTRODUCCIÓN. El decantarse por una carrera universitaria, es una decisión que marca el futuro profesional de los jóvenes; en ella están envueltas motivaciones intrínsecas, extrínsecas y expectativas que pueden predecir el desempeño académico. OBJETIVO. Predecir el rendimiento académico de los estudiantes de una facultad de enfermería, a través de los motivos intrínsecos, extrínsecos y expectativas para la elección de la carrera. METODOLOGÍA. Estudio correlacional, longitudinal, analítico. La muestra estuvo constituida por 400 estudiantes de primer semestre. Se aplicó una cédula socio demográfica; Escala de Motivación en Educación (EME); Escala de Expectativas Para la Elección de la Carrera e Interés Hacia los Estudios (EEPECIHE); Escala de Seguimiento Cambios en las Expectativas, Grado de Interés y Satisfacción de los Estudiantes (ESCEGIS). Los datos se analizaron con el software SPSS versión 25 para iOS; el estudio contó con la aprobación del comité de bioética en investigación de la Facultad de Enfermería Culiacán. RESULTADOS. Existen diferencias significativas de las motivaciones, expectativas y rendimiento académico (p <.05) al inicio del semestre y al finalizar el semestre; las motivaciones y expectativas predicen el rendimiento académico, en 74.6%, (R2=0,747, Ajuste R2 = 0,746,

Rinoplastia cerrada: una técnica vigente / Closed Rhinoplasty: a current technique

La rinoplastia cerrada es una cirugía que se realiza con el fin de cambiar la estructura de la nariz, con fines cosméticos o reparadores. Se busca realizar pequeños retoques que logren un aspecto natural. Es una de las cirugías estéticas más complejas y representa un reto para el cirujano, pues combina técnica con sensibilidad y ciencia con arte. En este artículo describimos esta técnica con el objetivo de demostrar su eficacia y vigencia, sin compararla con la rinoplastia abierta, pues no es motivo de discusión en este trabajo, por lo que no podemos asegurar que una opción es mejor o peor que la otra. Lo más conveniente es que los cirujanos estén capacitados para realizar cualquiera de estas. Con la rinoplastia cerrada se logran resultados que llenan las expectativas tanto de los pacientes, como de los cirujanos y el post operatorio es breve y prácticamente sin incidentes. Es una propuesta que tiene indicaciones precisas en el marco de una rinoplastia preservadora, que es tendencia a nivel mundial en la actualidad.

Closed rhinoplasty is a surgery that is performed in order to change the structure of the nose, for cosmetic or restorative purposes. It seeks to make small touches that achieve a natural appearance. It is one of the most complex cosmetic surgeries and represents a challenge for the surgeon, as it combines technique with sensitivity and science with art. In this article, we describe this technique in order to demonstrate its effectiveness and validity, without comparing it with open rhinoplasty, since it is not a matter of discussion in this work, so we cannot guarantee that one option is better or worse than the other. It is best if surgeons are trained to perform any of these. With closed rhinoplasty, results are achieved that meet the expectations of both patients and surgeons, and the postoperative period is brief and practically uneventful. It is a proposal that has precise indications within the framework of conservative rhinoplasty, which is currently a worldwide trend.

Automedicación y riesgo de abuso con benzodiacepinas en pacientes adultos Lima-Perú, 2019 / Self-medication and risk of abuse with benzodiazepines in adults patients Lima-Peru, 2019

RESUMEN: Introducción: Las benzodiacepinas tienen potencial para generar abuso, por lo que, un consumo indiscriminado, a través de la venta sin prescripción y la práctica de automedicación, significaría un alto riesgo, producto de su abuso. Objetivo: Establecer la relación entre la automedicación con benzodiacepinas y el riesgo de abuso en pacientes de un hospital de Lima-Perú. Metodología: Estudio transversal analítico. Se encuestó a 874 participantes, se usó una encuesta para determinar datos demográficos, uso de benzodiacepinas y preguntas de la prueba de detección de consumo de alcohol, tabaco y sustancias (ASSIST, por sus siglas en inglés); se obtuvo estadística descriptiva y analítica. Resultados: Hubo más encuestadas del sexo femenino (74,5%), la mediana de edades fue de 52 años (rango intercuartílico: 40-62 años). De los adultos estudiados, 485 fueron considerados como consumidores de benzodiacepinas con receta médica y 389 sin receta médica. Los consumidores con receta médica y sin receta médica que necesitaron tratamiento fueron 129 (26,6%) y 245 (63,0%), respectivamente (p<0.001). Conclusión: Hay una mayor prevalencia de personas que necesitan tratamiento por abuso en consumidores sin receta médica que en el grupo de consumidores con receta médica, por lo que, existe una relación significativa entre la automedicación con benzodiacepinas y el riesgo de abuso; lo que requiere tratamiento en la población estudiada.

ABSTRACT Introduction: Benzodiazepines have the potential to generate abuse, so an indiscriminate consumption, through the sale without prescription and the practice of self-medication, would mean a high risk due to their abuse. Objective: To establish the relationship between self-medication with benzodiazepines and the risk of abuse that requires treatment in adult patients of Hospital San Juan de Lurigancho, 2019. Methodology: It was an observational, correlational descriptive, transversal and prospective study. The sample size was 874 participants (95.0% confidence level; 80% power). Sampling was performed non-randomly. A survey was used to determine demographics, benzodiazepine use, and questions of Alcohol, Smoking and Substance Involvement Screening Test (ASSIST). Results: Of the study population, the most prevalent demographic data were female sex (74.5%), the median age was 52 years (interquartile range: 40-62 years), the age range 50-59 years (26.43%), married marital status (31.6%), secondary education level (48.4%) and occupation as a housewife (47.3%). Of adults studied, 485 were considered as consumers of benzodiazepines with prescription and 389 consumers without a prescription. Prescription and non-prescription consumers needing treatment were 129 (26.60%) and 245 (62.98%), respectively (p <0.001). Conclusion: There is a higher prevalence of people who need treatment for abuse in consumers without a prescription than in the group of consumers with a prescription so there is a significant relationship between self-medication with benzodiazepines and the risk of abuse that requires treatment in study population.

Circulating Osteogenic Progenitor Cells Enhanced with Teriparatide or Denosumab Treatment.

Circulating osteogenic precursor (COP) cells are peripheral blood cells with a capacity for osteogenesis. The objective of our study was to ascertain the percentage of COPs as an early biomarker of osteoporosis and the effect of these cells in response to Denosumab (DmAb) (anti-resorptive) or to Teriparatide (TPDP) (anabolic) as very effective drugs in the treatment of the illness. A first study was conducted on healthy volunteers, with three age ranges, to determine the percentage of COPs and relate it to their anthropometric and biochemical characteristics, followed by a second longitudinal study on patients with osteoporosis, whereby one group of patients was treated with TPTD and another with DmAb. All were analyzed by cytometry for COP percentage in blood, bone turnover markers, and bone mass. Our findings show that COPs are influenced by age and become more prolific in the stages of growth and skeletal maturation. A higher percentage of COPs is found in osteoporotic disease, which could constitute a predictive marker thereof. We also show how treatment with TPTD or DmAb mobilizes circulating osteogenic precursors in the blood. Significant increases in % COPs were observed after 12 months of treatment with Dmb (21.9%) and TPTD (17%). These results can be related to an increase in osteogenesis and, consequently, a better and more efficient repair of bone tissue.

Riesgo de diabetes mellitus según el cuestionario Finnish Diabetes Risk Score (FINDRISC) en Indígenas Warao de Barrancas del Orinoco, Monagas, Venezuela

Objetivo Determinar el Riesgo de diabetes mellitus según FINDRISC en indígenas Warao de Barrancas del Orinoco, Monagas, Venezuela. Metodología Se realizó un estudio observacional, descriptivo y de corte transversal en diciembre del 2015. El universo estuvo conformado por 213 indígenas y la muestra por 103 individuos. Se incluyeron pacientes sin diagnóstico de diabetes y mayores de 12 años. Se aplicó la encuesta FINDRISC. Los datos fueron agrupados y procesados por medio del programa estadístico SPSS, en el cual se aplicó la prueba estadística de chi-cuadrado de homogeneidad que arrojó un valor estadísticamente significativo de p<0,05. Resultados De 103 pacientes incluidos en el estudio, 57 eran del sexo femenino y 46 del masculino. Por sexo, el riesgo de diabetes con puntaje menor a 7 (leve) fue más frecuente en el masculino (63,0%) y el puntaje de 12-14 (riesgo moderado) fue similar en ambos sexos, sin diferencias estadísticamente significativas (p=0,37). La frecuencia de pacientes con 50 años y más con riesgo alto fue de 11,1%, seguido de los de 30-39 años, con 7,7%. El riesgo moderado (12-14 puntos) fue más frecuente en los pacientes con edades de 40-49 años, con un 44,4% y diferencias estadísticamente significativas por edad (p<0,00001). En general, los indígenas de la etnia Warao obtuvieron un riesgo alto de diabetes en el 3,9%, el riesgo moderado fue de 10,7% y más de la mitad obtuvo resultados de bajo riesgo, con 54,4%. Conclusión Los indígenas de la etnia Warao tienen un bajo riesgo de diabetes.

Objective To determine the risk of diabetes mellitus according to FINDRISC in Warao indigenous of Barrancas del Orinoco, Monagas, Venezuela. Methodology An observational, descriptive and cross-sectional study was carried out in December 2015. Universe was conformed by 213 natives and sample conformed by 103 individuals. Patients without diagnosis of diabetes and older than 12 years were included. The FINDRISC survey was applied. The data were grouped and processed by means of the statistical program SPSS, the statistical test of chi-square of homogeneity was applied and a value of p<0.05 was considered as statistically significant. Results Of 103 patients included in the study, 57 were female and 46 were male. By sex, the risk of diabetes with a score lower than 7 (mild) was more frequent in men (63.0%), the score of 12-14 (moderate risk) was similar in both sexes, with no statistically significant differences (p=0.37). The frequency of patients who were 50 years old and more at high risk was 11.1% followed by those aged 30-39 years with 7.7%. The moderate risk (12-14 points) was more frequent in patients aged 40-49 years old with 44.4%, with statistically significant differences being found by age (p<0.00001). In general, the indigenous people of the Warao ethnic group had a high risk of diabetes in 3.88%, the moderate risk was 10.7%, and more than half obtained low risk results with 54.4%. Conclusion The indigenous people of the Warao ethnic group have a low risk of diabetes.

Consumo de alimentos y actividad física en pacientes hipertensos de un centro de atención primaria / Food Consumption and Physical Activity in Hypertensive Patients from Primary Healthcare

Introducción: Con el estudio de las enfermedades cardiovasculares se ha logrado identificar las variables biológicas y estilos de vida, lo que ha permitido que la hipertensión arterial y sus complicaciones sean prevenibles y controlables. Objetivo: Determinar la frecuencia del consumo de alimentos y actividad física en pacientes hipertensos del Centro de Atención Primaria III Huaycán, Lima, Perú. Métodos: Se realizó un estudio observacional descriptivo, transversal y cuantitativo en pacientes hipertensos pertenecientes al programa del adulto mayor. Se recolectaron datos sociodemográficos, antropometría y presión arterial. Se aplicó el cuestionario internacional de actividad física y frecuencia de consumo de alimentos. Se analizaron estadísticas descriptivas, prueba de Chi cuadrado, ANOVA y Rho Spearman en SPSS 23. Resultados: Se evaluaron 570 pacientes, 61,8 por ciento pertenecía al sexo femenino, 39,5 por ciento tenía estudios de secundaria, 65,3 por ciento consumía antihipertensivos regularmente. La media del índice de masa corporal para mujeres fue 28,23±4,66 kg/m2. La presión arterial sistólica para el sexo masculino fue 132,89±13,42 mmHg y para el femenino, de 130,92±13,19 mmHg. El 13,5 por ciento tenía obesidad y cifras tensionales hipertensivas, 71,1 por ciento consumía pollo, 77,2 por ciento pan, cereales, arroz, pastas y trigo todos los días a la semana, mientras que 50,9 por ciento consumía frituras cuatro días por semana; 44,7 por ciento tenía bajo nivel de actividad física y cifras tensionales hipertensivas (p = 0,03). Conclusiones: La alimentación en la población de estudio era diversa, basada en alta ingesta de carbohidratos y grasas. Se evidenció que las personas con menos actividad física tenían mayores cifras tensionales. Es de considerar que la dieta saludable y la actividad física son factores complementarios al tratamiento farmacológico para el control de estos pacientes(AU)

Introduction: The study of cardiovascular diseases has permitted the identification of biological variables and lifestyles, which, in turn, has made hypertension and its complications preventable and controllable. Objective: To determine the frequency of food consumption and physical activity in hypertensive patients in the primary care center III Huaycán, Lima, Peru. Methods: A descriptive, cross-sectional, observational and quantitative study was carried out with hypertensive patients belonging to the elderly program. Sociodemographic, anthropometric and blood pressure data were collected. The international questionnaire of physical activity and frequency of food consumption was applied. Descriptive statistics, chi-square test, ANOVA and Rho Spearman were analyzed using SPSS 23. Results: 570 patients were assessed: 61.8 percent were female, 39.5 percent had high school education, and 65.3 percent consumed antihypertensive drugs regularly. The mean body mass index for women was 28.23±4.66 kg/m2. Systolic blood pressure for the male sex was 132.89±13.42 mmHg and 130.92±13.19 mmHg for the female sex. 13.5 percent had obesity and hypertensive blood pressure levels, 71.1 percent ate chicken, 77.2 percent consumed bread, cereals, rice, pasta and wheat every day of the week, while 50.9 percent consumed fried foods four days a week. 44.7 percent had a low level of physical activity and hypertensive blood pressure levels (P=0.03). Conclusions: The diet in the study population was diverse, based on high intake of carbohydrates and fats. People who did less physical activity evidently showed higher blood pressure numbers. A healthy diet and physical activity are to be considered complementary factors to pharmacological treatment for controlling these patients(AU)

Unraveling the Ca-P species produced over the time during phosphorus removal from aqueous solution using biocomposite of eggshell-palm mesocarp fiber.

Phosphorus (P) adsorption from aqueous solutions is usually evaluated by monitoring the P concentration and employed kinetic models. In this work, three adsorbents obtained from eggshell (ES) and eggshell mixed with palm mesocarp fiber (ESF-1:1 and ESF-1:10) at different Ca(OH)2/CaCO3 compositions were evaluated, and the Ca-P species formed monitored as a function of time deconvoluting Fourier Transform Infrared (FTIR) spectra. At 0.25 h the ESF-1:10 (Ca(OH)2: 26.2 wt%) exhibited better adsorption performance of 35 mgg-1 while ESF-1:1 and ES (Ca(OH)2: 2.8 and 3.0 wt%) showed 26 and 4 mgg-1, respectively. Characteristic PO43- bands in apatite were corroborated by XRD and FTIR. It was found that the role of Ca(OH)2 in the adsorption ends before 0.25 h, and thereafter CaCO3 becomes the phase responsible for the removal of orthophosphate H2PO4-/HPO42-/PO43- ions. The results indicate a direct ligand exchange of CO32- for PO43- that takes place while increasing the apatite crystallinity. On the other hand, the P adsorption process is also dependent on P concentration. At low P concentrations, characteristic bands of PO43- in apatite were observed in FTIR, while at high concentrations, characteristic bands for adsorbed HPO42- were obtained. The obtained results give a relevant role to CaCO3 in P adsorption. Kinetic analysis for Ca-based biocomposites showed that the Avrami order kinetic model fits better for the adsorbents. For P adsorption isotherm process the Langmuir's isotherms showed a good fit, with a maximum adsorption capacity of 90.8, 134.0, and 67.9 mgg-1 for ES, ESF-1:1, and ESF-1:10, respectively.

Species-level ichthyoplankton dynamics for 97 fishes in two major river basins of the Amazon using quantitative metabarcoding.

The Amazon basin holds the world's largest freshwater fish diversity. Information on the intensity and timing of reproductive ecology of Amazonian fish is scant. We use a metabarcoding method by capture using a single probe to quantify species-level ichthyoplankton dynamics. We sampled the Marañón and the Ucayali rivers in Peru monthly for 2 years. We identified 97 species that spawned mainly during the flood start, the flood end or the receding periods, although some species had spawning activity in more than one period. This information was new for 40 of the species in the Amazon basin and 80 species in Peru. Most species ceased spawning for a month during a strong hydrological anomaly in January 2016, demonstrating the rapidity with which they react to environmental modifications during the breeding season. We also document another unreported event in the Amazon basin, the inverse phenology of species belonging to one genus (Triportheus). Overall larval flow in the Marañón was more than twice that of the Ucayali, including for most commercial species (between two and 20 times higher), whereas the Ucayali accounts for ~80% of the fisheries landings in the region. Our results are discussed in the light of the main anthropogenic threats to fishes, hydropower dam construction and the Hidrovía Amazónica, and should serve as a pre-impact baseline.

Integral analysis of environmental and economic performance of combined agricultural intensification & bioenergy production in the Orinoquia region.

Agricultural intensification is a key strategy to help meet increasing demand for food and bioenergy. It has the potential to reduce direct and indirect land use change (LUC) and associated environmental impacts while contributing to a favorable economic performance of the agriculture sector. We conduct an integral analysis of environmental and economic impacts of LUC from projected agricultural intensification and bioenergy production in the Orinoquia region in 2030. We compare three agricultural intensification scenarios (low, medium, high) and a reference scenario, which assumes a business-as-usual development of agricultural production. The results show that with current inefficient management or with only very little intensification between 26% and 93% of the existing natural vegetation areas will be converted to agricultural land to meet increasing food demand. This results in the loss of biodiversity by 53% and increased water consumption by 111%. In the medium and high scenarios, the intensification allows meeting increased food demand within current agricultural lands and even generating surplus land which can be used to produce bioenergy crops. This results in the reduction of biodiversity loss by 8-13% with medium and high levels of intensification compared to the situation in 2018. Also, a positive economic performance is observed, stemming primarily from intensification of cattle production and additional energy crop production. Despite increasing irrigation efficiency in more intensive production systems, the water demand for perennial crops and cattle production over the dry season increases significantly, thus sustainable management practices that target efficient water use are needed. Agricultural productivity improvements, particularly for cattle production, are crucial for reducing the pressure on natural areas from increasing demand for both food products and bioenergy. This implies targeted investments in the agricultural sector and integrated planning of land use. Our results showed that production intensification in the Orinoquia region is a mechanism that could reduce the pressure on natural land and its associated environmental and economic impacts.

Age validation and contrasted growth performances of Pseudoplatystoma punctifer (Siluriformes: Pimelodidae) in two river systems of the Western Amazon

The doncella Pseudoplatystoma punctifer is an economically and ecologically important catfish in the Amazon basin. However, little is known about its age, growth and population dynamics parameters. This study aims to validate the formation of growth marks in vertebrae of individuals collected from two rivers systems of the Peruvian Amazon (Amazon-Marañón-Ucayali and Putumayo) and compare growth parameters using the von Bertalanffy growth function between sexes and systems. A total of 372 individuals from the Amazon-Marañón-Ucayali (AMU) system and 93 from the Putumayo River were analyzed. The formation of one growth ring per year was validated and the individual ages ranged from zero to nine years old. Females grew significantly larger than males in both systems. Both females and males grew significantly better in the AMU system than in the Putumayo River. Maximum observed length and size at maturity in the AMU system were lower than those reported in previous studies in the area, and together with an important proportion of juveniles in the catches, suggest that the species is heavily exploited. Further studies on the reproductive biology and population dynamics of the doncella are needed in order to implement management measures more in line with the current situation.(AU)

La doncella Pseudoplatystoma punctifer es un bagre de importancia económica y ecológica en la cuenca Amazonica. Pese a ello, poco se conoce acerca de parámetros de edad, crecimiento y dinámica poblacional. Este estudio tuvo como objetivo validar la formación de marcas de crecimiento en vértebras de individuos colectados en dos sistemas fluviales de la Amazonia Peruana (Amazonas-Marañón-Ucayali y Putumayo) y comparar los parámetros de crecimiento usando la función de von Bertalanffy entre sexos y sistemas. Fueron analizados 372 individuos del sistema Amazonas-Marañón-Ucayali (AMU) y 93 del Putumayo. Se validó la formación de un anillo de crecimiento por año, la edad osciló entre cero y nueve años. Las hembras fueron significativamente más grandes que los machos en ambos sistemas. Para ambos sexos el crecimiento fue significativamente mayor en el sistema AMU que en el Putumayo. Las máximas tallas y edades de primera madurez observadas en el sistema AMU fueron menores a las reportadas en estudios previos en el área, y junto con un considerable porcentaje de juveniles presentes en las capturas, se sugiere que la especie está siendo fuertemente explotada. Son necesarios estudios de biología reproductiva y dinámica poblacional de doncella para implementar medidas de manejo acordes a la situación actual.(AU)

Impact on reproductive performance and body condition in a small limpet parasitized by a large castrator pea crab.

Parasitic castrators utilize the energy reserves that the host allocates on reproduction resulting in sterilization of the host. However, whether other processes (e.g., growth) are also impaired depends on the balance between the castrator's energy requirements and the available resources that the castrated host does not use in reproduction. We investigated whether the castrator pea crab Calytraeotheres garthi alters body condition, reproductive performance, and occurrence of copulation in its limpet host Bostrycapulus odites. For this purpose, we examined the anatomy of the ovary, the seminal receptacles, and the body condition of parasitized and unparasitized limpets. The histology of the female gonad of parasitized limpets revealed the ovarian tubules are smaller and characterized by a greater proportion of intertubular and intratubular free space compared with non-parasitized individuals. The body condition of female limpets from all sizes (during summer) and those larger than ~16 mm (during spring and autumn) were impacted by the pea crab. These results are in contrast to that previously reported in the comparatively larger limpet species Crepidula cachimilla, in which the same pea crab species does not alter or even increase the host body weight. We concluded this pea crab species could drastically impair its host's reproduction and body condition although deleterious effects are species-specific and likely depend on limpet body size. The histology of seminal receptacles revealed an uncommon disposition of spermatozoa (i.e., excessive debris and acrosomes detached from epithelium) in seminal receptacles of some parasitized limpets. However, this analysis failed to determine whether sperm derived from present matings or previous pea crab infection. Further studies are needed to address whether pea crabs interfere with the mating behavior of limpets and if the alterations in sperm disposition are a consequence of castration.

Trends, structural changes, and assessment of time series models for forecasting hospital discharge due to death at a Mexican tertiary care hospital.

BACKGROUND: Data on hospital discharges can be used as a valuable instrument for hospital planning and management. The quantification of deaths can be considered a measure of the effectiveness of hospital intervention, and a high percentage of hospital discharges due to death can be associated with deficiencies in the quality of hospital care. OBJECTIVE: To determine the overall percentage of hospital discharges due to death in a Mexican tertiary care hospital from its opening, to describe the characteristics of the time series generated from the monthly percentage of hospital discharges due to death and to make and evaluate predictions. METHODS: This was a retrospective study involving the medical records of 81,083 patients who were discharged from a tertiary care hospital from April 2007 to December 2019 (first 153 months of operation). The records of the first 129 months (April 2007 to December 2017) were used for the analysis and construction of the models (training dataset). In addition, the records of the last 24 months (January 2018 to December 2019) were used to evaluate the predictions made (test dataset). Structural change was identified (Chow test), ARIMA models were adjusted, predictions were estimated with and without considering the structural change, and predictions were evaluated using error indices (MAE, RMSE, MAPE, and MASE). RESULTS: The total percentage of discharges due to death was 3.41%. A structural change was observed in the time series (March 2009, p>0.001), and ARIMA(0,0,0)(1,1,2)12 with drift models were adjusted with and without consideration of the structural change. The error metrics favored the model that did not consider the structural change (MAE = 0.63, RMSE = 0.81, MAPE = 25.89%, and MASE = 0.65). CONCLUSION: Our study suggests that the ARIMA models are an adequate tool for future monitoring of the monthly percentage of hospital discharges due to death, allowing us to detect observations that depart from the described trend and identify future structural changes.

Percepción sobre la capacitación universitaria en investigación médica: Un estudio Latinoamericano / Perception about university training in medical research: A Latin American study

Introducción: El desarrollo científico es considerado un componente de la educación médica debido a la implicancia de la investigación en la formación profesional, no existe verdadera educación superior sin investigación activa. Objetivo: Analizar la percepción de los estudiantes de medicina de Latinoamérica sobre la capacitación universitaria en investigación científica. Materiales y métodos: Se realizó un estudio observacional, descriptivo, de corte transversal, donde fueron incluidos 488 estudiantes de medicina de doce países de Latinoamérica. Se aplicó una encuesta estructurada mediante un formulario en línea de 10 preguntas, dividida en dos secciones: la primera, con las variables sociodemográficas, y la segunda, sobre la percepción de la capacitación estudiantil con una escala tipo Likert de cinco valores categóricos. Resultados: La edad estuvo comprendida de 17 a 34 años con una media de 22,34 años y un desvió estándar de 2.76, El 99,8% consideró importante la capacitación universitaria en temas de investigación científica. Conclusión: La mayoría de los estudiantes consideró importante recibir capacitación en sus universidades en temas como lectura crítica, redacción científica, búsqueda bibliográfica, metodología de la investigación y bioestadística. En general, la percepción sobre la capacitación recibida fue de regular a deficiente.

Introduction: Scientific development is considered a component of medical education, due to the implication of research to professional training there is no truly higher education without active research. Objectives: To analyze the perception of medical students in Latin America about university training in scientific research. Materials and methods: An observational, descriptive, cross-sectional study was conducted where 488 medical students from 12 Latin American countries were included. A structured questionnaire was applied using an online form of 10 questions, divided into two sections: the first one with the sociodemographic variables, and the second one about the perception of student training with a Likert scale of five categorical values. Results: The age ranged from 17 to 34 years with an average of 22.34 years and a standard deviation of 2.76. 99.8% considered important university training in scientific research topics. Conclusion: The majority of students consider it important to receive training in their universities on topics such as critical reading, scientific writing, bibliographic search, research methodology and biostatistics. In general, the perception of the training received is from regular to deficient.

Annual rhythms of temporal niche partitioning in the Sparidae family are correlated to different environmental variables.

The seasonal timing of recurring biological processes is essential for organisms living in temperate regions. While ample knowledge of these processes exists for terrestrial environments, seasonal timing in the marine environment is relatively understudied. Here, we characterized the annual rhythm of habitat use in six fish species belonging to the Sparidae family, highlighting the main environmental variables that correlate to such rhythms. The study was conducted at a coastal artificial reef through a cabled observatory system, which allowed gathering underwater time-lapse images every 30 minutes consecutively over 3 years. Rhythms of fish counts had a significant annual periodicity in four out of the six studied species. Species-specific temporal patterns were found, demonstrating a clear annual temporal niche partitioning within the studied family. Temperature was the most important environmental variable correlated with fish counts in the proximity of the artificial reef, while daily photoperiod and salinity were not important. In a scenario of human-induced rapid environmental change, tracking phenological shifts may provide key indications about the effects of climate change at both species and ecosystem level. Our study reinforces the efficacy of underwater cabled video-observatories as a reliable tool for long-term monitoring of phenological events.

Age and growth of the Amazonian migratory catfish Brachyplatystoma rousseauxii in the Madeira River basin before the construction of dams

The goliath catfish Brachyplatystoma rousseauxii has crucial economical and ecological functions in the Amazon basin. Although its life history characteristics have been studied in the Amazon, there is little information in the Madeira River basin, which holds genetically distinct populations and where dams were recently built. Using fish collected in Bolivia, Brazil and Peru, this study provides a validation of growth rings deposition and details the growth patterns of B. rousseauxii in the Madeira before the dams' construction. Age structure and growth parameters were determined from 497 otolith readings. The species exhibits two growth rings per year and sampled fish were between 0 and 16 years old. In the Brazilian portion of the basin, mainly young individuals below 5 years old were found, whereas older fish (> 5 years) were caught only in the Bolivian and Peruvian stretches, indicating that after migrating upstream to reproduce, adults remain in the headwaters of the Madeira River. Comparing with previous publications, B. rousseauxii had a slower growth and 20 cm lower maximum standard length in the Madeira River than in the Amazon River. This study provides a baseline for future evaluation of changes in population dynamics of the species following dams closure.(AU)

Brachyplatystoma rousseauxii é um bagre de importante papel econômico e ecológico na bacia amazônica. Embora existam estudos acerca de sua história de vida na Amazônia, há pouca informação para a bacia do rio Madeira, onde existem populações geneticamente distintas e recentemente foram construídas duas usinas hidrelétricas. Este estudo validou a deposição das marcas de crescimento e detalhou os padrões de desenvolvimento dessa espécie no rio Madeira, antes da construção das barragens. As coletas abrangeram os territórios brasileiro, boliviano e peruano, com estrutura etária e parâmetros de crescimento determinados a partir de 497 otólitos. Foram observadas duas marcas de crescimento por ano e indivíduos entre 0 e 16 anos. Na porção brasileira foram encontrados principalmente jovens menores de 5 anos, enquanto que os peixes mais velhos (> 5 anos) foram capturados apenas na Bolívia e Peru, indicando que após a migração reprodutiva, os adultos permanecem nas cabeceiras do rio Madeira. Comparando com estudos prévios realizados na calha principal do rio Amazonas, B. rousseauxii apresentou crescimento mais lento e comprimento padrão máximo inferior de 20 cm no rio Madeira. Este estudo fornece uma base para a avaliação futura das mudanças na dinâmica populacional desse espécie após o implementação das barragens.(AU)